ISIS's notorious executioner "Jihadi John" has reportedly fled the terrorist group and is on the run in war-torn Syria and may have joined another terrorist group.

Mohammed Emwazi, a British Kuwaiti computer science graduate turned murderer, is believed to have left the terrorist group after becoming fearful he might be killed by ISIS's chiefs.

The British terrorist has not been seen in a propaganda video for nearly six months after the horrific beheading of Japanese photojournalist Kenji Goto.

Questions over Emwazi's whereabouts have developed following his sudden disappearance from the spotlight in late January.

It is thought that the media pressure associated with being the masked executioner and the publicity surrounding his real identity may have led to Emwazi's surprise decision to leave ISIS, Daily Mail reports.

Emwazi has long been considered a high value target and was the standout figure in ISIS's brutal media strategy to terrify both the world.

Now ISIS chiefs are thought to have decided that Emwazi has become dispensable and no longer a necessary player in the terrorist group, a 'source' told the Mirror.

Speaking to MailOnline, Mr Kaderbhai research fellow at the ICSR said it 'does not make sense to think that they would ‘drop him like a stone’ – it’s not like he’s a captured Westerner who has lost propaganda value.

Regarding "Jihadi John's" disappearance from the endless ISIS propaganda video, Mr Kaderbhai suggested it may indicate that ISIS have 'nothing high profile to show off.'

The news comes after rumours that "Jihadi John" had been moved by ISIS to Libya, where he supposedly attended a terror training camp with Sousse gunman Seifeddine Rezgui.

Besides beheading Japanese 47-year-old photojournalist, he had previously been seen beheading American journalists James Foley and Steven Sotloff as well as murdering aid workers Alan Henning, David Haines and Peter Kassig.