LONDON (AP) -- A British-accented militant who has appeared in beheading videos released by the Islamic State group in Syria bears strong similarities to a man who grew up in London, a Muslim lobbying group said Thursday.
Mohammed Emwazi has been identified by news organizations as the masked militant more commonly known as "Jihadi John."
Asim Qureshi of CAGE, a London-based group which works with Muslims in conflict with British intelligence services, said Thursday he saw strong similarities, but because of the hood worn by the militant, "I can't be 100 percent certain."
The Center for the Study of Radicalization and Political Violence at King's College London, which closely tracks fighters in Syria, also said it believed the identification was correct.
British counterterrorism officials wouldn't confirm the man's identity. National Security Council spokeswoman Bernadette Meehan also said the U.S. couldn't confirm or deny the identity.
Masked, knife-wielding "Jihadi John" appeared in a video released in August showing the slaying of American journalist James Foley, denouncing the West before the killing. Former IS captives identified him as one of a group of British militants that prisoners had nicknamed "The Beatles."
A man with similar stature and voice also featured in videos of the killings of American journalist Steven Sotloff, Britons David Haines and Alan Hemming and U.S. aid worker Abdul-Rahman Kassig.
According to The Washington Post and the BBC, Emwazi was born in Kuwait, grew up in west London and studied computer programming at the University of Westminster. The university confirmed that a student of that name graduated in 2009.
"If these allegations are true, we are shocked and sickened by the news," the university said in a statement.
The news outlets said Emwazi had been known to Britain's intelligence services before he traveled to Syria in 2012.
Qureshi said Emwazi first contacted CAGE in 2009. Emwazi said he had traveled to Tanzania with two other men after leaving university, but was deported and questioned in Amsterdam by British and Dutch intelligence services.
The following year, Emwazi accused British intelligence services of preventing him from traveling to the country of his birth, Kuwait, where he planned to marry.
CAGE quoted an email Emwazi had sent saying, "I had a job waiting for me and marriage to get started. But now I feel like a prisoner, only not in a cage, in London."
"The Mohammed that I knew was extremely kind, extremely gentle, extremely soft-spoken, was the most humble young person that I knew," Qureshi said.
He said he hadn't had contact with Emwazi since January 2012.
Qureshi accused British authorities of alienating and radicalizing young British Muslims with heavy-handed policies.
"When we treat people as if they are outsiders, they will inevitably feel like outsiders," he said.
No one answered the door at the brick row house in west London where the Emwazi family is alleged to have lived. Neighbors in the surrounding area of public housing projects either declined comment or said they didn't know the family.
Neighbor Janine Kintenda, 47, who said she'd lived in the area for 16 years, was shocked at the news.
"Oh my God," she said, lifting her hand to her mouth. "This is bad. This is bad."
Shiraz Maher of the King's College radicalization center said he was investigating whether Emwazi was among a group of young West Londoners who traveled to Syria in about 2012.
Many of them are now dead, including Mohammad el-Araj, Ibrahim al-Mazwagi and Choukri Ellekhlifi, all killed in 2013.
He said Emwazi's background was similar to that of other British jihadis, and disproved the idea "that these guys are all impoverished, that they're coming from deprived backgrounds."
"They are by and large upwardly mobile people, well educated," he said.
Associated Press writers Raphael Satter and Danica Kirka contributed to this report.
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