The Belgian fathers who lost their sons in Syria
Two Belgian fathers who spent the last few weeks searching for their sons in northern Syria have gone home without them. The BBC's Duncan Crawford spoke to them in Turkey before they boarded a flight back to Belgium.
Sitting in the lobby of an old Turkish hotel in the border city of Gaziantep, Idriss Boutalliss is on the verge of tears.
"I still want to see my son," he says. "But it's difficult. He's with Isis."
The 45-year-old from Kortrijk, Belgium spent 10 days in northern Syria trying to get 19-year-old Abdelmalek, who is diabetic, to leave the jihadi group and return home.
"I managed to get to Raqqa and I met different Isis leaders," Mr Boutalliss says, describing how he saw Isis Amirs (leaders) in various "offices" in the city, as well as a Russian father who was also looking for his son.
Mr Boutalliss was travelling with another Belgian dad, Pol Van Hessche, whose son, 18-year-old Lucas, also travelled to Syria last month.
"One Amir (Isis leader) said they were in Suluk, which is near to Raqqa. We travelled there and finally met one leader who gave us permission to see our sons," says Mr Boutalliss.
He says the teenagers - who are best friends - are being taught a strict brand of Sharia law in a house with Europeans and other nationalities.
Masked Isis guards carrying rifles allowed Abdelmalek and Lucas to speak to the two fathers, but both sons refused to leave.
"Abdelmalek said: 'I don't want to leave. I'm not going back to Belgium because the police will immediately put me into prison'," says Mr Boutalliss.
'He needs medicine'
He gave his son insulin for his diabetes, but fears the worst, as he does not believe the medication is available in Syria.
"He can't live without the medicine. A diabetic needs insulin four times a day. If he doesn't get any insulin, he'll be dead straight away," Mr Boutalliss says.
After the meeting, the two sons stayed with Isis and the other father, Mr Van Hessche, returned to Turkey. Mr Boutalliss decided to remain in Syria, hoping that he might be able see the teenagers again and change their minds.
He lived with a Syrian family in the town of Manbij, not far from Raqqa.
Raqqa is Isis's headquarters, where they have implemented an extreme interpretation of Islamic Sharia law, with punishments including beheadings and crucifixions.
The city has also seen fierce violence between Isis and rival groups fighting the forces of Syrian President Bashar al-Assad.
"I didn't see any cruel things. I didn't see anyone being crucified on a cross," says Mr Boutalliss, who is desperate to get his son home.
The jihadi group has been accused of serious abuses while it attempts to set up an Islamic caliphate across parts of Syria and Iraq.
Despite Mr Boutalliss spending a week trying to re-initiate contact with his son, he heard nothing.
He was informed that the road to Raqqa, and subsequent travel to Suluk to see the two teenagers, was too dangerous due to fighting in the area.
Frustrated and stressed, Mr Boutalliss crossed back into Turkey a few days ago.
"It's very difficult for me, I can't live without him," he says, holding back tears.
"My wife, the children, his brothers and sisters, they can't live without him. Without my son."
Idriss Boutalliss and Pol van Hessche have now left Turkey. At the time of writing, there had been no further contact from Abdelmalek or Lucas in Syria. Their trip was set up through the help of Dimitri Bontinck, a former Belgian soldier who rescued his own son from Syria last year.