The Islamic State militant group yesterday claimed responsibility for the murder of British aid worker Alan Henning in a video showing his apparent execution.

In the video, almost identical to those released after three previous murders, a masked IS militant also threatens a hostage he identifies as an American, Peter Kassig.

Both men were volunteers working to bring aid to civilian populations in Syria when they were captured.

Henning, was a driver in a humanitarian convoy organized by an Islamic charity.

Kassig, who is still alive at the end of the one-minute 11-second video, is a former US Army soldier who served in Iraq then returned to the Middle East to found a relief organisation.