The parents of a Muslim convert dubbed Jihadi Jack are facing jail after being found guilty of funding terrorism.

Organic farmer John Letts, 58, and former Oxfam fundraising officer Sally Lane, 57, refused to believe their 18-year-old son Jack had become a dangerous extremist when they allowed him to travel, the Old Bailey heard.

They ignored repeated warnings he had joined Islamic State in Syria and sent – or tried to send – a total of £1,723 for him despite being told by police three times not to.

Prosecutor Alison Morgan QC said the couple, from Oxford, “turned a blind eye to the obvious” – that their son had joined the murderous terrorist group by the time they sent £223 in September 2015.

The defendants claimed their son, who suffers from obsessive compulsive disorder, was trapped in Raqqa and by December 2015 when they tried to send more funds, they were acting under “duress” fearing he was in mortal danger.

A jury deliberated for nearly 20 hours to find the defendants guilty of one charge of funding terrorism in in September 2015 but not guilty of the same charge in December 2015.

Jurors were discharged after they were unable to decide on a third charge relating to an attempt to send money in January 2016.

Prosecutor Alison Morgan QC said the Crown would not seek a retrial and asked for the charge to lie on file.

There were gasps in the public gallery but defendants made no reaction in the dock.

The court had heard how Jack Letts left the family home in May 2014 and embarked on what his parents saw as a “grand adventure” to learn Arabic in Jordan.

Before his departure, a friend of the teenager had tried to warn his parents about his growing extremism and urged them to confiscate his passport.

From Jordan, Jack Letts moved to Kuwait and married Asmaa, the daughter of a tribal elder, in Iraq before travelling on to Syria.

Lane told jurors she was “horrified” when he rang her to say he was in Syria in September 2014.

She said: “I screamed at him, ‘How could you be so stupid? You will get killed. You will be beheaded’.”

John Letts begged his son to come home, telling him: “A father should never live to see his son buried.”

He went on to accuse him of being a “pawn … helping spread hatred, pain, anger, suffering and violence”, jurors heard.

In early 2015, police raided the family home and warned the defendants not to send any property or money to their son.

Jack Letts ranted about it to his parents, saying police would “die in your rage”.

In July 2015, he posted on Facebook that he would like to perform a “martyrdom operation” on a group of British soldiers, and threatened to behead his old school friend Linus Doubtfire, who had joined the Army.

When challenged by his parents, he said: “I would happily kill each and every one of Linus Unit personally… I honestly want to cut Linus head off.”

Ms Morgan said it was “ridiculous” to claim the message had been posted by someone else using Jack Letts’s account, because he even knew the name of the family cat.

At the time, Lane conceded in a message to her son it was “naive of us to believe” he was not a fighter.

The defendants also consulted an academic expert who told them it was “highly improbable” that Jack Letts had not engaged in military activity, the court heard.

In spite of the mounting evidence,  Lane sent £223 after Jack Letts gave her his word the money would have “nothing to do with jihad”.

Police followed up with a second warning, telling Lane that “sending money to Jack is the same as sending money to Isis”.

But in December 2015, Jack Letts began indicating he would like to leave Syria and told of a “big misguidance in the state”.

John Letts told a family liaison officer that Jack Letts was “desperate to get out” and in “danger”, and was advised he could send him money to leave.

The advice was quickly corrected and the defendants were issued with a written notice stating: “The police do not endorse or authorise the sending of any monies to Jack Letts.”

Lane told her son: “We know you are in danger so we feel we have no choice but to help you and send it.”

But when she asked him to spell out the danger he was in, Jack Letts responded: “Define danger.”

She went on to attempt two money transfers which were blocked, and the defendants were arrested.

John Letts declined to give evidence, but his barrister Henry Blaxland QC told jurors the prosecution was “inhumane to the point of being cruel”.

He said: “These parents have to all intents and purposes lost their son. They are having to deal with the trauma.”

The jury was not told that father-of-one Jack Letts, now aged 23, is being held by Kurdish authorities in northern Syria accused of being a member of IS.

Detective Chief Superintendent Kath Barnes said the conviction sends a clear message, adding: “It’s not for us to choose which laws to follow and which not to and when it’s OK to break the law.”

She said investigators had a “huge empathy” for the Letts family, adding: “Fundamentally John Letts and Sally Lane are not bad people.

“It’s hard to imagine the kind of agony they must be going through because of the choices their son made.”

A Muslim convert dubbed Jihadi Jack ranted about decapitating an old school friend after finding out he was in the British Army, a court has heard.

Despite Jack Letts’ apparent online outburst about Linus Doubtfire, his supportive parents still tried to help him, the Old Bailey was told.

Organic farmer John Letts, 58, and his wife Sally Lane, 56, are on trial accused of sending or trying to send sums totalling GBP 1,723 to their son even though they had every reason to believe he had joined Islamic State in Syria.

Jack Letts had left the family home in Oxford in 2014 aged 18, the court heard.

His mother, a former fundraising and marketing officer, had bought him a flight to Jordan, despite a warning that he planned to go and fight in Syria, the court heard.

From there, he travelled to Kuwait and then on to Iraq and Syria, the jury was told.

On October 1 2014, Lane told one of her son’s friends he was “OK for now” but “in the worst place possible and doesn’t want to leave”.

The next day, Letts revealed to a friend that he was “over there” in an “Isis area” but not fighting.

He allegedly said: “It sounds like he’s having the adventure of a lifetime.”

By early 2015, the defendants knew their son had married in Iraq and had no intention of returning to Britain, jurors heard.

John Letts accused his son of lying about his plans to leave and said he was a “pawn… helping to spread hatred, pain, anger, suffering and violence”.

In March 2015, police visited the defendants and formally warned them they risked prosecution if they sent their son property or money, jurors were told.

When he found out about the raid, Jack Letts allegedly responded:

“Please convey to the British police that I’m not planning on coming back to their broken country.

“Convey to them from me ‘Die in your rage soon you’ll be the ones being raided!'”

In May, he posted a picture of himself standing on the Taqba Dam in Raqqa, the heartland of IS territory, jurors were told.

In July, Mr Doubtfire posted a picture on Facebook as he completed his Commando Artillery Course in the British Army.

Letts commented: “I would love to perform a martyrdom operation in this scene.”

Prosecutor Alison Morgan QC said the defendants appeared shocked by his Facebook post.

Lane allegedly urged him not to be “so stupid”, saying: “How did we bring you up to be so easily manipulated?”

He responded: “I admit it was wrong if I seemed like I was joking. I genuinely believe attacking the British Army is a very praiseworthy action when the intention is correct.

“I would happily kill each and every one of Linus Unit personally.

“This message for you, Mum and (younger brother) Tyler, I honestly want to cut Linus head off.

“I hope he finds himself lost in Beji or Fallujah one day and sees me whilst I’m armed and I put six bullets in his head.”

His mother replied: “I’m really hoping that your disgusting comments about cutting people’s heads off are not coming from you, i.e. someone else is using your account.”

Ms Morgan said the significance of the exchange was that the defendants were never sure they were communicating directly with their son, let alone that the transfers they went on to make would go to him or what the money would be used for.

On September 2 2015, Lane allegedly transferred money to an account in Lebanon after her son insisted it had “nothing to do with jihad”.

She allegedly told him: “I would go to prison for you if I thought it gave you a better chance of actually reaching your 25th birthday.”

In October, she told him: “Clearly I indulged you, I made you think you were the centre of the universe. I regret this bitterly.

“I was a terrible parent that gave you too much power as a child – I should have made you adapt to the world, instead of adapting myself to your world. I have done you no favours by doing this.”

She said he showed signs of “mental illness”, adding: “I have to bear some responsibility for that as your mother.”

In a police interview in November, Lane denied helping terrorists, saying she hoped the money she sent would pay for her son to get glasses.

John Letts and Lane, of Chilswell Road, Oxford, have denied three charges of funding terrorism.

The man nicknamed Jihadi Jack has said that he wants to return to Britain, but he thinks it unlikely he will be allowed back.

Jack Letts, 23, speaking from the Kurdish jail where he has been held for two years on suspicion of joining IS after he ran away to Syria in 2014, said he missed his mum, pasties, and Doctor Who.

He told ITV News: “I feel British, I am British.

“If the UK accepted me I would go back to the UK, but I don’t think that’s going to happen.”

Born in Oxford, the Muslim convert also has a Canadian passport thanks to his father’s nationality, but admitted: “I don’t know if that will still be valid.”

He told the broadcaster that he had lived on “the Oxford Street of Raqqa”, and married an Iraqi woman who has given birth to the couple’s son.

Mr Letts, a former pupil of Cherwell School, also confessed that he was pleased when he first heard news of the Paris terror attacks in 2015, and blamed his reaction on his experiences of coalition airstrikes in Raqqa.

He said when asked about the Bataclan atrocities: “At the time, I thought it was a good thing.

“At the time we had this idea, living in Raqqa, getting bombed every five minutes by coalition jets. I’ve seen children burnt alive.

“You have this idea of ‘why shouldn’t it happen to them?'”

But he claimed he has since had a change of heart, and sympathy for the innocent people killed, as he “realised that they had nothing to do with it”.

The Home Office said: “In recent days the Home Secretary has clearly stated that his priority is the safety and security of Britain and the people who live here.

“In order to protect this country, he has the power to deprive someone of their British citizenship where it would not render them stateless.

“We do not comment on individual cases, but any decisions to deprive individuals of their citizenship are based on all available evidence and not taken lightly.”

Mr Letts, who was a teenager when he fled to Syria, has not seen his parents in half a decade, and is missing some elements of his life in the UK.

He added: “I miss people mostly, I miss my mum. Five years I haven’t seen my mum, two years I haven’t spoken to my mum.

“I miss pasties. And Doctor Who.”

Mr Letts’ parents, John Letts and Sally Lane, from Chilswell Road, Oxford, are awaiting trial in the UK accused of sending money to their son.

They have denied three charges of funding terrorism.

This is not the first time Mr Letts has spoken to the British media since he fled his home.

In 2016, he told Channel 4 News that he missed Krispy Kreme doughnuts and kebabs, and had narrowly survived an airstrike with just a “scratch”.

And when asked if he was an IS fighter, he replied “Currently I’m not” before saying later in a statement that he opposes the militant group.

Mr Letts’ interview comes the day after the family of Islamic State bride Shamima Begum confirmed they would be challenging the Home Office’s decision to revoke the 19-year-old’s British citizenship.

Ms Begum was one of three schoolgirls to leave Bethnal Green to join the terror cult in 2015 and recently gave birth to a baby boy, her third child.

They said in a letter to the Home Secretary on Thursday: “We must, therefore, assist Shamima in challenging your decision to take away the one thing that is her only hope at rehabilitation, her British citizenship.”