Heavy Backlash Rained On The Uk Security Service - British Prime Minister Gives Excusses Why Jihadi John Wasn't Stopped From Leaving The UK

The prime minister has defended the security services amid criticisms they failed to stop Mohammed Emwazi, known as 'Jihadi John', from joining Islamic State in Syria.

David Cameron said the security services made "incredibly difficult judgements" on the UK's behalf.

His comments came after it emerged Emwazi was known to authorities.

The PM said he would not comment on specific cases but urged the public to back the security services.

Emwazi, who is in his mid-20s, first appeared in a video last August, when he apparently killed the US journalist James Foley.

He was later thought to have been pictured in the videos of the beheadings of British aid worker David Haines, US journalist Steven Sotloff, British taxi driver Alan Henning, and American aid worker Abdul-Rahman Kassig, also known as Peter.