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Barcelona: Terrorists were plotting larger attacks in Spain

Barcelona terror attack: Major manhunt continues [photos] Close

A policeman stands by a car involved in a terrorist attack in Cambrils, a city 120 kilometres south of Barcelona, on August 18, 2017.
'Alleged terrorists' drove into pedestrians in the Spanish seaside resort of Cambrils early August 18 before being shot dead by security forces, just hours after a similar attack in nearby Barcelona. / AFP PHOTO / LLUIS GENELLUIS GENE/AFP/Getty Images

A policeman stands by a car involved in a terrorist attack in Cambrils, a city 120 kilometres south of Barcelona, on August 18, 2017. 'Alleged terrorists' drove into pedestrians in the Spanish seaside resort of Cambrils early August 18 before being shot dead by security forces, just hours after a similar attack in nearby Barcelona. / AFP PHOTO / LLUIS GENELLUIS GENE/AFP/Getty Images

AFP/Getty Images

A policeman stands by a car involved in a terrorist attack in Cambrils, a city 120 kilometres south of Barcelona, on August 18, 2017.
'Alleged terrorists' drove into pedestrians in the Spanish seaside resort of Cambrils early August 18 before being shot dead by security forces, just hours after a similar attack in nearby Barcelona. / AFP PHOTO / LLUIS GENELLUIS GENE/AFP/Getty Images

A policeman stands by a car involved in a terrorist attack in Cambrils, a city 120 kilometres south of Barcelona, on August 18, 2017. 'Alleged terrorists' drove into pedestrians in the Spanish seaside resort of Cambrils early August 18 before being shot dead by security forces, just hours after a similar attack in nearby Barcelona. / AFP PHOTO / LLUIS GENELLUIS GENE/AFP/Getty Images

AFP/Getty Images

The lights of the Eiffel Tower in the French capital Paris are switched off on August 17, 2017, in solidarity with neighbouring Spain following two quick-succession, separate attacks in Barcelona and another popular Spanish seaside city Cambrils, a city 120 kilometres south of Barcelona, leaving 13 people dead and injuring more than 100 others.
There were at least 18 nationalities among the Barcelona victims who came from countries as varied as France, Venezuela, Australia, Ireland, Peru, Algeria and China, according to Spain's civil protection agency. / AFP PHOTO / Zakaria ABDELKAFIZAKARIA ABDELKAFI/AFP/Getty Images

The lights of the Eiffel Tower in the French capital Paris are switched off on August 17, 2017, in solidarity with neighbouring Spain following two quick-succession, separate attacks in Barcelona and another popular Spanish seaside city Cambrils, a city 120 kilometres south of Barcelona, leaving 13 people dead and injuring more than 100 others. There were at least 18 nationalities among the Barcelona victims who came from countries as varied as France, Venezuela, Australia, Ireland, Peru, Algeria and China, according to Spain's civil protection agency. / AFP PHOTO / Zakaria ABDELKAFIZAKARIA ABDELKAFI/AFP/Getty Images

AFP/Getty Images

A police officer touches his face in Las Ramblas, in Barcelona, Spain, Friday, Aug. 18, 2017. A white van jumped up onto a sidewalk and sped down a pedestrian zone Thursday in Barcelona's historic Las Ramblas district, swerving from side to side as it plowed into tourists and residents. Police said 13 people were killed and more than 50 wounded in what they called a terror attack.(AP Photo/Manu Fernandez)

A police officer touches his face in Las Ramblas, in Barcelona, Spain, Friday, Aug. 18, 2017. A white van jumped up onto a sidewalk and sped down a pedestrian zone Thursday in Barcelona's historic Las Ramblas district, swerving from side to side as it plowed into tourists and residents. Police said 13 people were killed and more than 50 wounded in what they called a terror attack.(AP Photo/Manu Fernandez)

AP

BARCELONA, SPAIN - AUGUST 17:  A damaged van, believed to be the one used in the attack, is surrounded by police officers in the Las Ramblas area on August 17, 2017 in Barcelona, Spain. Officials say 13 people are confirmed dead and at least 50 injured after a van plowed into people in the Las Ramblas area of the city this afternoon. (Photo by David Ramos/Getty Images) ***BESTPIX***

BARCELONA, SPAIN - AUGUST 17: A damaged van, believed to be the one used in the attack, is surrounded by police officers in the Las Ramblas area on August 17, 2017 in Barcelona, Spain. Officials say 13 people are confirmed dead and at least 50 injured after a van plowed into people in the Las Ramblas area of the city this afternoon. (Photo by David Ramos/Getty Images) ***BESTPIX***

People flee from the scene after a white van jumped the sidewalk in the historic Las Ramblas district of Barcelona, Spain, crashing into a summer crowd of residents and tourists Thursday, Aug. 17, 2017.   According to witnesses the white van swerved from side to side as it plowed into tourists and residents. (AP Photo/Giannis Papanikos)

People flee from the scene after a white van jumped the sidewalk in the historic Las Ramblas district of Barcelona, Spain, crashing into a summer crowd of residents and tourists Thursday, Aug. 17, 2017. According to witnesses the white van swerved from side to side as it plowed into tourists and residents. (AP Photo/Giannis Papanikos)

AP

Armed police officers stand next to their van in Las Ramblas, in Barcelona, Spain, Friday, Aug. 18, 2017. A white van jumped up onto a sidewalk and sped down a pedestrian zone Thursday in Barcelona's historic Las Ramblas district, swerving from side to side as it plowed into tourists and residents. Police said 13 people were killed and more than 50 wounded in what they called a terror attack.(AP Photo/Manu Fernandez)

Armed police officers stand next to their van in Las Ramblas, in Barcelona, Spain, Friday, Aug. 18, 2017. A white van jumped up onto a sidewalk and sped down a pedestrian zone Thursday in Barcelona's historic Las Ramblas district, swerving from side to side as it plowed into tourists and residents. Police said 13 people were killed and more than 50 wounded in what they called a terror attack.(AP Photo/Manu Fernandez)

AP

Members of the NYPD Counterterrorism Unit stand guard in Time Square as security is increased as a result of a attack in Barcelona, Spain earlier on Thursday, Aug. 17, 2017, at in New York. (AP Photo/Michael Noble Jr.)

Members of the NYPD Counterterrorism Unit stand guard in Time Square as security is increased as a result of a attack in Barcelona, Spain earlier on Thursday, Aug. 17, 2017, at in New York. (AP Photo/Michael Noble Jr.)

AP

Policemen check the area after police killed five attackers in Cambrils near Tarragona on August 18, 2017.
Drivers have ploughed into pedestrians in two quick-succession, separate attacks in Barcelona and another popular Spanish seaside city, leaving 13 people dead and injuring more than 100 others. The incident in Cambrils injured six civilians -- one of them critical -- and a police officer, authorities said.  / AFP PHOTO / LLUIS GENELLUIS GENE/AFP/Getty Images

Policemen check the area after police killed five attackers in Cambrils near Tarragona on August 18, 2017. Drivers have ploughed into pedestrians in two quick-succession, separate attacks in Barcelona and another popular Spanish seaside city, leaving 13 people dead and injuring more than 100 others. The incident in Cambrils injured six civilians -- one of them critical -- and a police officer, authorities said. / AFP PHOTO / LLUIS GENELLUIS GENE/AFP/Getty Images

AFP/Getty Images

Policemen check the area after police killed five attackers in Cambrils near Tarragona on August 18, 2017.
Drivers have ploughed into pedestrians in two quick-succession, separate attacks in Barcelona and another popular Spanish seaside city, leaving 13 people dead and injuring more than 100 others. The incident in Cambrils injured six civilians -- one of them critical -- and a police officer, authorities said.  / AFP PHOTO / LLUIS GENELLUIS GENE/AFP/Getty Images

Policemen check the area after police killed five attackers in Cambrils near Tarragona on August 18, 2017. Drivers have ploughed into pedestrians in two quick-succession, separate attacks in Barcelona and another popular Spanish seaside city, leaving 13 people dead and injuring more than 100 others. The incident in Cambrils injured six civilians -- one of them critical -- and a police officer, authorities said. / AFP PHOTO / LLUIS GENELLUIS GENE/AFP/Getty Images

AFP/Getty Images

The lights of One World Trade Center are lit in the colors of the Spanish flag to honor the victims of the Barcelona terror attack on August 17, 2017 in New York.
A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack" and a police source said one suspect had left the scene and was "holed up in a bar". The police source said they were hunting for a total of two suspects. / AFP PHOTO / Bryan R. SmithBRYAN R. SMITH/AFP/Getty Images

The lights of One World Trade Center are lit in the colors of the Spanish flag to honor the victims of the Barcelona terror attack on August 17, 2017 in New York. A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack" and a police source said one suspect had left the scene and was "holed up in a bar". The police source said they were hunting for a total of two suspects. / AFP PHOTO / Bryan R. SmithBRYAN R. SMITH/AFP/Getty Images

AFP/Getty Images

The lights of One World Trade Center are lit in the colors of the Spanish flag to honor the victims of the Barcelona terror attack on August 17, 2017 in New York.
A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack" and a police source said one suspect had left the scene and was "holed up in a bar". The police source said they were hunting for a total of two suspects. / AFP PHOTO / Bryan R. SmithBRYAN R. SMITH/AFP/Getty Images

The lights of One World Trade Center are lit in the colors of the Spanish flag to honor the victims of the Barcelona terror attack on August 17, 2017 in New York. A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack" and a police source said one suspect had left the scene and was "holed up in a bar". The police source said they were hunting for a total of two suspects. / AFP PHOTO / Bryan R. SmithBRYAN R. SMITH/AFP/Getty Images

AFP/Getty Images

Policemen check the area after towing away the van which ploughed into the crowd, killing at least 13 people and injuring around 100 others on the Rambla in Barcelona, on August 18, 2017.
A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. 
Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack". The driver of a van that mowed into a packed street in Barcelona is still on the run, Spanish police said. / AFP PHOTO / Josep LAGOJOSEP LAGO/AFP/Getty Images

Policemen check the area after towing away the van which ploughed into the crowd, killing at least 13 people and injuring around 100 others on the Rambla in Barcelona, on August 18, 2017. A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack". The driver of a van that mowed into a packed street in Barcelona is still on the run, Spanish police said. / AFP PHOTO / Josep LAGOJOSEP LAGO/AFP/Getty Images

AFP/Getty Images

Policemen check the area after towing away the van which ploughed into the crowd, killing at least 13 people and injuring around 100 others on the Rambla in Barcelona, on August 18, 2017.
A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. 
Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack". The driver of a van that mowed into a packed street in Barcelona is still on the run, Spanish police said. / AFP PHOTO / Josep LAGOJOSEP LAGO/AFP/Getty Images

Policemen check the area after towing away the van which ploughed into the crowd, killing at least 13 people and injuring around 100 others on the Rambla in Barcelona, on August 18, 2017. A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack". The driver of a van that mowed into a packed street in Barcelona is still on the run, Spanish police said. / AFP PHOTO / Josep LAGOJOSEP LAGO/AFP/Getty Images

AFP/Getty Images

Tourists wait for the police to allow them to come back to their hotel on the Rambla boulevard after a van ploughed into the crowd, killing at least 13 people and injuring around 100 others is towed away from the Rambla in Barcelona, on August 18, 2017.
A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. 
Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack". The driver of a van that mowed into a packed street in Barcelona is still on the run, Spanish police said. / AFP PHOTO / JAVIER SORIANOJAVIER SORIANO/AFP/Getty Images

Tourists wait for the police to allow them to come back to their hotel on the Rambla boulevard after a van ploughed into the crowd, killing at least 13 people and injuring around 100 others is towed away from the Rambla in Barcelona, on August 18, 2017. A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack". The driver of a van that mowed into a packed street in Barcelona is still on the run, Spanish police said. / AFP PHOTO / JAVIER SORIANOJAVIER SORIANO/AFP/Getty Images

AFP/Getty Images

Tourists wait for the police to allow them to come back to their hotel on the Rambla boulevard after a van ploughed into the crowd, killing at least 13 people and injuring around 100 others on the Rambla in Barcelona, on August 18, 2017.
A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. 
Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack". The driver of a van that mowed into a packed street in Barcelona is still on the run, Spanish police said. / AFP PHOTO / JAVIER SORIANOJAVIER SORIANO/AFP/Getty Images

Tourists wait for the police to allow them to come back to their hotel on the Rambla boulevard after a van ploughed into the crowd, killing at least 13 people and injuring around 100 others on the Rambla in Barcelona, on August 18, 2017. A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack". The driver of a van that mowed into a packed street in Barcelona is still on the run, Spanish police said. / AFP PHOTO / JAVIER SORIANOJAVIER SORIANO/AFP/Getty Images

AFP/Getty Images

The van (farR) who ploughed into the crowd, killing at least 13 people and injuring around 100 others is seen momemts before being towed away from the Rambla in Barcelona on August 18, 2017.
A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. 
Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack". The driver of a van that mowed into a packed street in Barcelona is still on the run, Spanish police said. / AFP PHOTO / PAU BARRENAPAU BARRENA/AFP/Getty Images

The van (farR) who ploughed into the crowd, killing at least 13 people and injuring around 100 others is seen momemts before being towed away from the Rambla in Barcelona on August 18, 2017. A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack". The driver of a van that mowed into a packed street in Barcelona is still on the run, Spanish police said. / AFP PHOTO / PAU BARRENAPAU BARRENA/AFP/Getty Images

AFP/Getty Images

The van who ploughed into the crowd, killing at least 13 people and injuring around 100 others is towed away from the Rambla in Barcelona on August 18, 2017.
A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. 
Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack". The driver of a van that mowed into a packed street in Barcelona is still on the run, Spanish police said. / AFP PHOTO / Josep LAGOJOSEP LAGO/AFP/Getty Images

The van who ploughed into the crowd, killing at least 13 people and injuring around 100 others is towed away from the Rambla in Barcelona on August 18, 2017. A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack". The driver of a van that mowed into a packed street in Barcelona is still on the run, Spanish police said. / AFP PHOTO / Josep LAGOJOSEP LAGO/AFP/Getty Images

AFP/Getty Images

The van who ploughed into the crowd, killing at least 13 people and injuring around 100 others is towed away from the Rambla in Barcelona on August 18, 2017.
A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. 
Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack". The driver of a van that mowed into a packed street in Barcelona is still on the run, Spanish police said. / AFP PHOTO / JAVIER SORIANOJAVIER SORIANO/AFP/Getty Images

The van who ploughed into the crowd, killing at least 13 people and injuring around 100 others is towed away from the Rambla in Barcelona on August 18, 2017. A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack". The driver of a van that mowed into a packed street in Barcelona is still on the run, Spanish police said. / AFP PHOTO / JAVIER SORIANOJAVIER SORIANO/AFP/Getty Images

AFP/Getty Images

Barcelona's Mayor Ada Colau (C) and officials arrive on the Rambla boulevard after a van ploughed into the crowd, killing at least 13 people and injuring around 100 others on the Rambla in Barcelona on August 17, 2017.
A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. 
Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack". The driver of a van that mowed into a packed street in Barcelona is still on the run, Spanish police said. / AFP PHOTO / Josep LAGOJOSEP LAGO/AFP/Getty Images

Barcelona's Mayor Ada Colau (C) and officials arrive on the Rambla boulevard after a van ploughed into the crowd, killing at least 13 people and injuring around 100 others on the Rambla in Barcelona on August 17, 2017. A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack". The driver of a van that mowed into a packed street in Barcelona is still on the run, Spanish police said. / AFP PHOTO / Josep LAGOJOSEP LAGO/AFP/Getty Images

AFP/Getty Images

Barcelona's Mayor Ada Colau (C) arrives on the Rambla boulevard after a van ploughed into the crowd, killing at least 13 people and injuring around 100 others on the Rambla in Barcelona on August 17, 2017.
A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. 
Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack". The driver of a van that mowed into a packed street in Barcelona is still on the run, Spanish police said. / AFP PHOTO / Josep LAGOJOSEP LAGO/AFP/Getty Images

Barcelona's Mayor Ada Colau (C) arrives on the Rambla boulevard after a van ploughed into the crowd, killing at least 13 people and injuring around 100 others on the Rambla in Barcelona on August 17, 2017. A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack". The driver of a van that mowed into a packed street in Barcelona is still on the run, Spanish police said. / AFP PHOTO / Josep LAGOJOSEP LAGO/AFP/Getty Images

AFP/Getty Images

A police officer gestures, backdropped by an overturned car at the spot where terrorists were intercepted

A police officer gestures, backdropped by an overturned car at the spot where terrorists were intercepted

AP/PA Images

People take shelter inside a shop in Barcelona

People take shelter inside a shop in Barcelona

AP/PA Images

A man touches a newspaper displaying a photograph of the aftermath of the terror attack in Las Ramblas

A man touches a newspaper displaying a photograph of the aftermath of the terror attack in Las Ramblas

AP/PA Images

Emergency workers stand on a blocked street in Barcelona

Emergency workers stand on a blocked street in Barcelona

Distressing scenes in Las Ramblas area of Barcelona following the terror attack

Distressing scenes in Las Ramblas area of Barcelona following the terror attack

AP

Distressing scenes in Las Ramblas area of Barcelona following the terror attack

Distressing scenes in Las Ramblas area of Barcelona following the terror attack

AFP/Getty Images

Distressing scenes in Las Ramblas area of Barcelona following the terror attack

Distressing scenes in Las Ramblas area of Barcelona following the terror attack

Getty Images

A frightened father flees with his young child

A frightened father flees with his young child

AP

Distressing scenes in Las Ramblas area of Barcelona following the terror attack

Distressing scenes in Las Ramblas area of Barcelona following the terror attack

AP

A woman cries as she and a man are escorted by Spanish policemen outside a cordoned off area after a van ploughed into the crowd, killing 13 persons and injuring over 80 on the Rambla in Barcelona

A woman cries as she and a man are escorted by Spanish policemen outside a cordoned off area after a van ploughed into the crowd, killing 13 persons and injuring over 80 on the Rambla in Barcelona

AFP/Getty Images

Emergency crews tend to the injured after yesterday’s attack

Emergency crews tend to the injured after yesterday’s attack

Getty Images

An injured person is carried away in Barcelona

An injured person is carried away in Barcelona

AP/PA Images

Injured people are treated in Barcelona, Spain

Injured people are treated in Barcelona, Spain

An injured person is helped

An injured person is helped

AP/PA Images

Police officers tell pedestrians to leave the area

Police officers tell pedestrians to leave the area

AP/PA Images

Injured people are tended to by emergency services

Injured people are tended to by emergency services

AP/PA Images

Injured people are treated in Barcelona, Spain, Thursday, Aug. 17, 2017 after a white van jumped the sidewalk in the historic Las Ramblas district, crashing into a summer crowd of residents and tourists and injuring several people, police said. (AP Photo/Oriol Duran)

Injured people are treated in Barcelona, Spain, Thursday, Aug. 17, 2017 after a white van jumped the sidewalk in the historic Las Ramblas district, crashing into a summer crowd of residents and tourists and injuring several people, police said. (AP Photo/Oriol Duran)

AP

People flee the scene in Barcelona, Spain, Thursday, Aug. 17, 2017 after a white van jumped the sidewalk in the historic Las Ramblas district, crashing into a summer crowd of residents and tourists and injuring several people, police said. (AP Photo/Oriol Duran)

People flee the scene in Barcelona, Spain, Thursday, Aug. 17, 2017 after a white van jumped the sidewalk in the historic Las Ramblas district, crashing into a summer crowd of residents and tourists and injuring several people, police said. (AP Photo/Oriol Duran)

AP

Injured people are treated in Barcelona, Spain, Thursday, Aug. 17, 2017 after a white van jumped the sidewalk in the historic Las Ramblas district, crashing into a summer crowd of residents and tourists and injuring several people, police said. (AP Photo/Oriol Duran)

Injured people are treated in Barcelona, Spain, Thursday, Aug. 17, 2017 after a white van jumped the sidewalk in the historic Las Ramblas district, crashing into a summer crowd of residents and tourists and injuring several people, police said. (AP Photo/Oriol Duran)

AP

Police officers tell members of the public to leave the scene in a street in Barcelona, Spain, Thursday, Aug. 17, 2017. Police in the northern Spanish city of Barcelona say a white van has jumped the sidewalk in the city's historic Las Ramblas district, injuring several people. (AP Photo/Manu Fernandez)

Police officers tell members of the public to leave the scene in a street in Barcelona, Spain, Thursday, Aug. 17, 2017. Police in the northern Spanish city of Barcelona say a white van has jumped the sidewalk in the city's historic Las Ramblas district, injuring several people. (AP Photo/Manu Fernandez)

AP

Screengrab taken with permission from video posted on twitter by @pawilerma of the scene  in Las Ramblas, Barcelona after several people have been injured after a van crashed on a pavement in a popular tourist area of the Spanish city. Pawi Lerma/PA Wire

Screengrab taken with permission from video posted on twitter by @pawilerma of the scene in Las Ramblas, Barcelona after several people have been injured after a van crashed on a pavement in a popular tourist area of the Spanish city. Pawi Lerma/PA Wire

PA

Screengrab taken with permission from video posted on twitter by @pawilerma of the scene  in Las Ramblas, Barcelona after several people have been injured after a van crashed on a pavement in a popular tourist area of the Spanish city. Pawi Lerma/PA Wire

Screengrab taken with permission from video posted on twitter by @pawilerma of the scene in Las Ramblas, Barcelona after several people have been injured after a van crashed on a pavement in a popular tourist area of the Spanish city. Pawi Lerma/PA Wire

PA

A policeman stands by a car involved in a terrorist attack in Cambrils, a city 120 kilometres south of Barcelona, on August 18, 2017. 'Alleged terrorists' drove into pedestrians in the Spanish seaside resort of Cambrils early August 18 before being shot dead by security forces, just hours after a similar attack in nearby Barcelona. / AFP PHOTO / LLUIS GENELLUIS GENE/AFP/Getty Images

The terrorists behind deadly attacks in Spain that killed 14 people were preparing bigger atrocities than those they carried out, police said.

As a fourth arrest was made in connection with the deadly vehicle assaults in Barcelona and Cambrils, authorities revealed that a suspected gas explosion on Wednesday robbed the killers of materials to use in larger-scale operations.

Prime Minister Theresa May said a child with dual British nationality was believed to be among those unaccounted for, after a grandfather made a desperate online plea for information about his young grandson's whereabouts following the van attack in the Catalan capital.

Some 34 nationalities were among almost 130 people wounded in the attacks in Barcelona's popular Las Ramblas shopping area on Thursday and in Cambrils, a seaside town 70 miles to the south west, early on Friday.

Catalan regional police official Josep Lluis Trapero told reporters on Friday that Wednesday's blast at a house in Alcanar, a further 55 miles down the coast, meant the attacks were more "rudimentary" than planned.

Reports from Spain had earlier suggested the terror cell may have been planning an attack using gas canisters.

He said: "We are working on the hypothesis that these attacks were being prepared for a while around this private home in Alcanar.

"We think they were preparing at least one or more attacks in Barcelona.

"The explosion in Alcanar at least avoided some of the material they were counting on to carry out even bigger attacks than the ones that happened.

"Because of that the attack in Barcelona and the one in Cambrils were carried out in a bit more rudimentary way than the one they had initially planned."

He added that one of the five terrorists killed by police during the terror attack in Cambrils may have been the driver of the van which killed 13 people in Barcelona.

Four men are in custody, aged 21, 27, 28 and 34. Three are Moroccan and one Spanish, and police said none of them were previously known to the security services for terror-related reasons.

Meanwhile, the grandfather of seven-year-old Julian Alessandro Cadman made a plea for information about the boy, who became separated from his mother during the attack in Barcelona.

Tony Cadman, whose Facebook profile says he lives in Sydney and is from Gillingham, Dorset, posted a photograph of Julian, writing: "My grandson, Julian Alessandro Cadman is missing. Please like and share."

Speaking later from Chequers, Mrs May said: "The UK stands shoulder to shoulder with Spain in confronting and dealing with the evil of terrorism, and I have offered any assistance we can provide.

"Sadly I must tell you that we do believe that a number of British nationals were caught up in the attack and we are urgently looking into reports of a child believed missing, who is a British dual national."

The attacks in Barcelona and Cambrils, some 70 miles south-west of the city on the Mediterranean coast, took place around eight hours apart on Thursday afternoon and in the early hours of Friday.

In a chilling echo of the London Bridge attack in June, Catalonia president Carles Puigdemont said the five terrorists in the Cambrils car were wearing fake suicide belts when they were stopped.

Police revealed that an axe and knives were also found in the vehicle, with one of the latter used to wound one person in the face before the terrorists were gunned down.

Barcelona, a hugely popular tourist destination, came to a halt at noon on Friday as a minute's silence was observed in the Placa Catalunya, close to the scene of the attack.

Led by King Felipe and PM Mariano Rajoy, the silence was followed by applause for the victims.

Three days of mourning have been declared by the government of Catalonia.

The Queen sent a message of sympathy to King Filipe of Spain, saying: "It is deeply upsetting when innocent people are put at risk in this way when going about their daily lives."

Belfast Telegraph