A British-Canadian couple is pleading with the Canadian and U.K. governments for help getting their son out of a prison in Kurdish-held northern Syria.

Jack Letts, a Muslim convert from Oxford, England, has been imprisoned since May.

His father, John Letts, originally from Pain Court, Ont., said his 21-year-old son claimed he was being tortured when he and his British wife, Sally Lane, last spoke to him.

"I'm scared of electricity… I've actually been tortured… I can prove it," Jack said in correspondence which his parents shared with CBC News.

We don't really know he's alive. — John Letts , father

He also claimed he had been denied food and exercise and had been spending long periods of time in solitary confinement.

"It's quite hard to think of the child you loved who might, as we speak, be being tortured with electricity," said Letts in an interview with CBC, the family's first with a Canadian media outlet.

Letts said his son was trying to flee into Turkey from territory controlled by the Islamic State in Iraq and Syria (ISIS) when he was captured by security forces in northern Syria. They have charged him with being a member of ISIS.

For the first two months, Letts and Lane say the prison allowed regular contact with their son via text message and chat. But they said have had no communication since July 8.

"We don't really know he's alive," said Letts, an organic farmer.

The case has garnered considerable attention in the U.K. where he is often dubbed "Jihadi Jack."

A young Jack Letts, far right, with his father and his younger brother on a winter vacation near Ottawa. (Sally Allen)

'Reaching out'

Letts and Lane said the Kurdish officials have told them for months that they are willing to turn their son over to Canadian or British authorities. All they need is a formal request from either country.

Their first letter to Foreign Affairs Minister Chrystia Freeland was sent June 25. After a second letter on Sept. 19, Freeland replied the same day that she would follow up with her team.

This is not the way that a person in detention is handled. — Tayab Ali, human rights lawyer

But since then, though they remain in regular contact with Global Affairs Canada (GAC), Letts and Lane have been told only that Canada's diplomats are "reaching out" on the matter, but that efforts are hampered because Ottawa does not have a consulate in that region, which is known as both Rojava and the Democratic Federation of Northern Syria (DFNS).

The de facto autonomous region is allied with the U.S.-led coalition against ISIS, and opposes the Syrian regime of Bashar al-Assad.

In a statement to CBC News, GAC said it could not comment on the case because of privacy concerns.

British authorities also issued a statement saying that they do not have consular access in the region.

Human rights lawyer Tayab Ali claims his attempts to speak with Letts have been ignored by Kurdish authorities. (Jared Thomas/CBC)

'No official request'

Tayab Ali, a human rights lawyer in London who represents the family, says both governments have a duty to ensure Jack's well-being and that he is not being tortured.

"This is not the way that a person in detention is handled to an international legal standard. It's just not the way it's done," he said.

He says local authorities are flouting the Geneva Conventions and international human rights law by keeping him cut off from his family and lawyer; adding that not everybody who went to Syria and Iraq is a fighter or a terrorist.

"A lot of people who went there came straight back… because they realized that it wasn't really the promised land," he said.

Letts, second from right, left home in 2014 to study Arabic and later made his way into ISIS-controlled territory in Syria in Iraq. The whole family holds dual British-Canadian citizenship. (Photo submitted by Sally Lane)

But the European representative for the DFNS refutes the allegation that they are not complying with international law, and said they are willing to turn Letts over to Canadian or British authorities.

"However, so far there has been no official request from neither Canadian or British governments," Sinam Mohamad said in a statement.

Margaret Gilmore, a senior associate fellow with the Royal United Services Institute, a security think-tank, in London, says it's "odd" both governments have been so silent on the matter.

"There is a deep concern that something may have happened to him and they [his parents] are not being told the truth," said Gilmore.

Studied in Kuwait

John Letts said his son, a former A-student, flunked out of school after being diagnosed with obsessive compulsive disorder (OCD). In 2014, at age 18, he travelled to Jordan to visit a friend, and decided to study Arabic in Kuwait.

It's quite hard to think of the child you loved who might, as we speak, be being tortured with electricity — John Letts , father

Letts said he and Lane never opposed Jack's conversion to Islam and that they paid for his course.

"I thought it was a good thing to do Islamic studies. It's a beautiful language, it's a rich culture," he said.

Later that year, he made his way into ISIS-controlled areas of Iraq and Syria.

Both Letts and Lane were charged in 2016 under the U.K.'s Terrorism Act after attempting to send him £1,723 (about $2,900 Cdn) while he was there. They deny all charges, but a court order in the U.K. prevents reporting the details of their defence.

Must answer allegations

His parents say they cannot believe Letts was a member of ISIS. They say he spoke out against the extremist group.

"He told me, 'These people are not Islamic. This is not an Islamic system,'" said Letts.

Jack married an Iraqi woman during his travels and had a son with her, but somehow got separated from them and is not sure if they are still alive.

'We want nothing to do with Islamic fundamentalism,' says John Letts 1:10

"ISIS took my wife from me, I have more reason to hate them than anyone," he said in a message.

Letts and Lane say they would never condone their son being involved in terrorism, but if he was, he must face legal consequences.

"He should be brought back to Canada or to Britain or somewhere other than where he is, detained, questioned, investigated, put on trial," said Letts. "I don't think he'd ever be capable of doing what they claim that the jihadis do."

"We're in this… absurd situation where we're saying just let him speak for himself," said Lane.

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