Police say counter-terrorism bosses are investigating claims that a man from Oxford, labelled 'Jihadi Jack', has travelled to Syria to join so-called Islamic State.

John and Sally Letts, from Grandpont, South Oxford, said at the weekend they felt betrayed by claims their son, Jack Letts, 20, had become a fighter for the terrorist group.

Mr and Mrs Letts described their son as "kind, funny and gentle" and said he has reassured them he is not a member of Islamic State.

Thames Valley Police issued a statement today saying the South East Counter Terrorism Unit was aware of recent reports in the media regarding a 20-year-old man from Oxford travelling to Syria and it confirmed it was investigating.

The statement added: "This investigation began in March 2015 and is ongoing.

"We are unable to comment in any specifics regarding the investigation but would like to say that anyone who knows of someone who may be potentially vulnerable to being drawn into terrorist-related activity, including travelling abroad to conflict zones should contact local police for advice and support on 101."

Further information is available on the national Prevent Tragedies website preventtragedies.co.uk

If you see or hear something that you are concerned could be terrorist related, call the Anti-Terrorist Hotline on 0800 789 321.