At least 100 people have been killed after a passenger plane crashed on take-off at Madrid's Barajas Airport. Estimates of the final toll ranged up to 150, with only 20 escaping alive.
Many others were injured when the plane bound for Gran Canaria skidded off the runway.
Spanair flight JK5022 was carrying 164 adult passengers, two babies and nine crew members.
Spain's Interior Ministry confirmed that over 100 people have died. Rescue workers at the scene said that figure could be closer to 150.
The flight was bound for Las Palmas in the Canary Islands.
It is understood the plane, an MD-82 narrowbody aircraft, manufactured by Boeing unit McDonnell Douglas, burst into flames after leaving the runway on take-off.
Spanish newspaper El Pais reported that the disaster occurred during a second attempt at take off.
Some observers said one of the left engines caught fire as the plane accelerated, causing it to swing off track.
Spanish media are reporting that the plane broke into two parts.
At the airport, helicopters and fire trucks dumped water on the plane, which ended up in a wooded area at the end of the runway at Terminal 4.
An official with the Madrid emergency rescue service SAMUR said crews were removing bodies and injured people from the plane.
"It is catastrophe," he said.
"There was clearly a problem - the plane fell to the ground and clearly there are many, many injured. There is an emergency plan for many injured and we have organised a special area for ambulances."
A member of Spain's civil guard said: "It doesn't look anything like a plane - it's horrific - everything is burnt.
"This is the closest thing to hell that I've seen. The bodies were boiling, we burnt ourselves collecting them."
The airline issued a statement saying: "Spanair regrets to confirm that its flight number JK 5022 from Madrid to Las Palmas de Gran Canarias was involved in an accident at Madrid, at 1445 hours local time today.
"The aircraft, an MD-82, was en route from Madrid to Las Palmas when the accident occurred, at 14:23 hours local time. We can confirm that there were 166 passengers onboard."
A statement from Boeing said: "Boeing extends its deep condolences to the families and friends of those lost in the crash of Spanair 5022 in Madrid, and our hope for the speedy recovery of the injured.
"We stand ready to provide technical assistance to the Spanish Comisión de Investigación de Accidentes e Incidentes de Aviación Civil (CIAIAC) as it investigates the accident."
Weather conditions in Madrid were fine at the time of the incident.
Aviation Herald reports that the same aircraft had technical trouble four days ago: "A Spanair McDonnell Douglas MD-82, registration EC-HFS performing flight JK5113 from Lanzarote,CI to Madrid,SP (Spain), diverted to Las Palmas,CI (Spain) due to a generator failure about 30 minutes into the flight.
"Air Traffic Control understood, that an engine had failed and activated a full emergency response. The landing was normal, passengers disembarked normally. After repairs the flight resumed and arrived in Madrid with a delay of 4 hours."
The last major Spanish accident involving a major airline was in Bilbao in 1985 when 148 people died as their plane crashed while approaching the city's airport.
People concerned for friends or relatives who may have been on board the plane can call Spanair's helpline on: +34 800 400 200.