Islamic State (IS) militants have released a video of the killing of five men who it claims were spying for the UK.
The 10 minute video has a masked man with a British accent threatening attacks in the UK, saying it is a message for British Prime Minister David Cameron, BBC reports.
The man is seen standing behind five hostages in orange jumpsuits, and points a gun at the camera saying there will be an invasion of IS fighters in Europe.
The hostages allegedly confess to completing reconnaissance missions for British authorities, The Guardian reports, and then they are murdered.
A boy later appears talking about killing "unbelievers".
The UK Foreign Office is examining the video. It has not been independently authenticated.