The parents of "Jihadi Jack" have pleaded for the British government to allow him home after pictures were published of conditions inside the prisons holding Islamic State suspects.

Prisoners were seen lying tightly packed on the floor of a cell wearing orange jumpsuits in footage broadcast on the US network CBS last month.

Jack Letts, a Muslim convert from Oxfordshire was stripped of his UK citizenship after travelling to the Middle East to join Islamic State of Iraq and the Levant (Isil).

His mother Sally Lane told The Mail On Sunday: "If there is evidence he has committed a crime, then bring him home and put him on trial, and if he is guilty, send him to prison.

"But he has been in this limbo for two-and-a-half years with no end in sight."

She said they believed the man in the photo was their 23-year-old-son, however, the Telegraph has been told the detainee is not Letts. The paper understands the photo is likely a Chechen fighter of similar appearance.

Jack has visible, large scars up his left arm and his stomach from an injury he sustained several years ago. There are no such marks on the detainee in the picture.