A British doctor who travelled to Syria to volunteer has died in detention there, according to his family.

Abbas Khan, 32, an orthopaedic surgeon from south London, had been told he would be released at the end of the week.

It is not known how he died, although there are reports that Syrian government officials have said Khan committed suicide.

The doctor’s brother, however, told the BBC that it was “impossible” that Khan would have taken his own life when he was so close to being freed.

The British Foreign Office said it was “extremely concerned” by the reports of his death.

Khan travelled to the war-torn Syrian city of Aleppo last year to treat wounded civilians. He was arrested within days of arriving.