Jack Letts
Jack Letts near the Tabqa Dam, Syria, which he posted on Facebook Facebook

The parents of a British man reported to have travelled to Syria to join Islamic State (IS) have revealed they were arrested after sending him money to buy food and new glasses. Jack Letts, 20, was labelled "Jihadi Jack" after pictures showed him in the Syrian city of Raqqa, the self-declared capital of IS.

A Muslim-convert from Oxford, he was suspected of being the first white Briton to join the terrorist group having left his home in 2014. Jack and his parents insist he has not signed up as an Islamist fighter, however, and claim he is carrying out "humanitarian work".

In an interview with Channel 4 News yesterday (4 February), parents John Letts and Sally Lane said their son suffered from obsessive compulsive disorder (OCD) and feared he would not leave Syria alive. The couple spoke of their despair after being arrested under the Terrorism Act when they tried to send him money because he had complained of being cold, hungry and of needing new glasses.

"I think it's crazy that we can't send a penny to our ill son to help him because we'll be seen as supporting terrorism," said his father, an organic farmer. "Your child's about to fall off a cliff, and they're holding you back even though he's crawling forward to the edge."

His mother, an administrator, added: "It's the worst feeling in the world. You feel completely helpless. Your child's out there, they have no support, they're still reliant on you, he's sending desperate messages saying it's cold and he doesn't have food or he can't see, and legally we're not allowed to help him."

Their son's journey, from a middle-class childhood in England to living in IS-controlled areas of Syria, has led to speculation he had become radicalised after converting to Islam. The couple, both atheists, says there's no evidence he had become a jihadist fighter and say he left for Syria before the rise of IS.

According to some media reports, Letts was 18-years old when he secretly travelled to Syria, while informing his parents that he was headed to Kuwait to study Arabic. Letts was in the Syrian city of Raqqa before moving to the Iraqi city of Fallujah, where he was said to be a front-line fighter for Daesh, The Daily Mail reported. He also reportedly has an Iraqi wife and son named Muhammed.

However, his parents claim he is the victim of misinformation.

His mother said: "We've directly asked him. I know people will say 'he'll lie to you', but we know he won't lie about his religion because anything to do with his religion he thinks he'll go straight to hell.

"I think if he was a fighter, Jack's the sort of person who would tell us, and most of the people out there who are fighting are quite open that they're fighting."

Jack Letts attended Cherwell School and was said to be well-liked by his peers, known among friends as the "class clown". He dropped out of sixth form when he started having trouble reading and concentrating, symptoms of what doctors would later diagnose as OCD. The condition ended his dream of becoming a doctor, his parents said.

John Letts said after his son converted to Islam, his religion helped him cope with his illness. He insists Jack's decision to go to Syria was motivated by a humanitarian concern for the people there.

He said: "Islam gave him a lot of comfort. He was really concerned about thousands and thousands of people dying of starvation and being barrel bombed in Syria. So am I, and if that makes you a radical, then I'm a radical."

The police confirmed officers had arrested the couple after they sent their son money. The pair, who last heard from Jack a week ago, said they transferred him funds after receiving messages from him complaining he was cold, hungry and couldn't see because he had no glasses.

South East Counter Terrorism Command said in a statement that it was aware of "recent reports in the media regarding a 20-year-old man from Oxford travelling to Syria and can confirm we are investigating".

It added: "We can confirm a 55-year-old man and a 53-year-old woman, from Oxford, were arrested on suspicion of sending money to Syria which could be used for terrorism purposes, and were bailed until 17 February."

Sally Lane said she just wanted her son "to come home", with father John Letts adding: "I think it will probably end badly. I don't want it to end badly... it's my first son."