Police have been searching the home of a Labour councillor whose son is one of nine Britons arrested in Turkey on suspicion of trying to cross the border into Syria.
Shakil Ahmed said he thought his son Waheed had been in Birmingham on a work placement when he discovered that he was one of five adults and four children being held by Turkish authorities after they were stopped in Hatay province on Wednesday.
Police were yesterday searching Mr Ahmed's home for clues as to why Waheed had travelled to the country.
The Foreign and Commonwealth Office was unable to confirm when the nine people, who are related, would reach British soil, but Sky News reported they are to be deported over the weekend.
Greater Manchester Police (GMP) said officers were trying to establish their reason for travelling to the Syrian border.
The group includes two women aged 47 and 22, three men aged 24, 22 and 21, and four children aged one, three, eight and 11, GMP said.
Footage apparently showed the Britons arriving at a police station in southern Hatay province, where they were understood to have been kept overnight.
The force said it had uncovered "no evidence whatsoever" of any imminent threat to the Rochdale community or elsewhere in the UK.
Mr Ahmed, a councillor who represents the Kingsway ward on Rochdale Borough Council, has spoken of his shock at his son's arrest.
In a statement after news of the arrests broke he said: "I was shocked, worried and extremely upset to hear that my son has been arrested on the Turkey-Syria border.
"It's a total mystery to me why he's there, as I was under the impression he was on a work placement in Birmingham.
"My son is a good Muslim and his loyalties belong to Britain, so I don't understand what he's doing there. If I thought for a second that he was in danger of being radicalised, I would have reported him to the authorities.
"He's studying a degree in politics and sociology at Manchester University and has a good future ahead of him. I just want to speak to my son and get him home as soon as possible so I can find out what's going on."
He was later reported to have said the group had been on holiday.
Assistant Chief Constable Ian Wiggett said: "What is obviously concerning is why a family were seemingly attempting to take very young and vulnerable children into a war zone. Such a volatile and dangerous environment is no place for them whatsoever."
The latest Britons to be detained follow three young men who were stopped at the Turkey-Syria border last month. They were tracked down after police were given a tip-off about their alleged plan to enter the country.
A woman was also arrested at the border on a separate occasion last month.
In February, police launched an international manhunt for three schoolgirls who went missing from their east London homes.
Bethnal Green Academy pupils Shamima Begum, Amira Abase and Kadiza Sultana are believed to be inside Syria after flying to Turkey on a well-trodden path to the country.
It is understood they were following another 15-year-old girl who travelled there in December.
A High Court judge has since confiscated the passports of four other pupils at the school after concerns were raised by Tower Hamlets Council.
The Metropolitan Police believe around 600 Britons have travelled to Syria and Iraq since the conflict began, while around half are believed to have returned to the UK.