Islamic State executioner ‘Jihadi John’ has been identified in reports as a London-based computer programming graduate.
According to the Washington Post, the IS militant has been named by friends and others familiar with the case as Mohammed Emwazi.
British radicalisation experts said they believed the identity to be “accurate and correct”.
The man nicknamed as Jihadi John rose to notoriety after he first appeared in a video posted online last August, in which he appeared to kill the American journalist James Foley.
A statement from the International Centre for the Study of Radicalisation (ICSR) at King’s College London said: “We believe the identity and name published by the Washington Post and now in the public realm to be accurate and correct.”
Dressed all in black with a balaclava covering all but his eyes and the ridge of his nose and a holster under his left arm, ‘Jihadi John’ reappeared in videos of the beheadings of US journalist Steven Sotloff, British aid workers David Haines and Alan Henning, and American aid worker Peter Kassig.
And last month, the militant appeared in a video with the Japanese hostages Haruna Yukawa and Kenji Goto, shortly before they were killed.
A detailed Washington Post article claims Jihadi John is in fact Kuwaiti-born Emwazi, who it says travelled to Syria around 2012 before later joining IS, which has taken control of large swathes of the conflict-torn country, as well as territory in neighbouring Iraq.
The article claims Emwazi started to radicalise after a planned safari in Tanzania following his graduation from the University of Westminster was brought to an abrupt end when he was detained on arrival in Dar es Salaam and deported the following day.
It is claimed that he told friends he was flown to Amsterdam where an officer from MI5 accused him of trying to reach Somalia, where the militant group al-Shabab operates.
According to the article, in 2009/2010, Emwazi decided to move to Kuwait, where he told friends he had a job and marriage waiting for him – but was prevented from travelling there by UK counter-terrorism officials.
Released hostages have told officials that Jihadi John was part of a team guarding Western captives at a prison in Idlib, Syria, in 2013. He was joined by two other men with British accents, including one who was dubbed “George”.
The ICSR said: “Jihadi John is not special in the sense that all the foreign fighters have tried to hide their identity by using pseudonyms or literally by masking themselves.
“The fact that ‘Jihadi John’ has been unveiled in this manner demonstrates that whatever efforts are made, the ability to mask one’s identity is limited or in fact impossible, and their true identities will eventually be revealed.
“This demonstrates what we have long said about radicalisation, that it is not something driven by poverty or social deprivation. Ideology clearly plays a big role in motivating some men to participate in jihadist causes.
“British fighters have clearly demonstrated that they are not in this conflict to take a back seat. They are full participants in this war, operating as suicide bombers, hostage takers, and executioners.”
Scotland Yard has refused to confirm the reports.
Commander Richard Walton, head of the Met’s counter terrorism command, said: “We have previously asked media outlets not to speculate about the details of our investigation on the basis that life is at risk.
“We are not going to confirm the identity of anyone at this stage or give an update on the progress of this live counter-terrorism investigation.”
Downing Street declined to confirm or deny that the reported name was known to the intelligence and security services.
Asked if David Cameron was concerned about Emwazi’s name being reported, a No 10 spokeswoman said: “The Prime Minister would be concerned about information being put into the public domain at any time that might jeopardise ongoing police or security investigations or the safety of British citizens.
“There is an ongoing investigation. It is absolutely right that we allow the police and security agencies to do all they can to bring those responsible to justice and to help keep British people safe.”