Sniper: I see those I killed in flashbacks

Sergeant Craig Harrison served as a soldier in the Army between 1991 and 2014 and has been described as the world's most accurate sniper.

In November 2009, he shot dead two Taliban fighters, who were just over 1.5 miles away from him and who were firing at soldiers in his regiment.

But his experiences on the battlefield have left him badly traumatised.

He suffers from post-traumatic stress disorder and told the BBC's Victoria Derbyshire that he sees the faces of those he killed in flashbacks and when he closes his eyes.

Watch the full version of this story here on Victoria Derbyshire weekdays from 09:15-11:00 BST on BBC Two, the BBC News Channel and online.