UK Prime Minister David Cameron has said he wants the British terrorist nicknamed Jihadi John to face justice, after reports that he was injured in an allied air strike against Islamic State (IS) commanders in Iraq.

The masked fanatic with a London accent, believed to be responsible for the beheading of two British and two American hostages, is reported to have been taken to hospital after narrowly escaping death in the raid.

The Prime Minister declined to comment on the specific operation, but said the message should go out to anyone considering travelling to Syria or Iraq to fight for the militant group that they are "putting themselves in harm's way".

Speaking at a press conference at the G20 summit in Australia, Mr Cameron said: "You should be in no doubt that I want Jihadi John to face justice for the appalling acts that have been carried out in Syria, but I wouldn't make any comment on individual issues and strikes.

"The point is clear that if people travel to Syria or Iraq in order to conduct terror operations against British people, British citizens or people back here in Britain, then they are putting themselves in harm's way and they shouldn't be in any doubt about that."

Reports suggested that Jihadi John was injured in a US-led air strike last weekend on a summit of IS leaders in the town of Al Qaim, in Anbar province, near Iraq's border with Syria.