LONDON (AP) - The world knows him as "Jihadi John," the masked, knife-wielding militant in videos showing Western hostages being beheaded by the Islamic State group. A growing body of evidence suggests he is a London-raised university graduate, described by one man who knew him as kind, gentle and humble.
The Washington Post and the BBC on Thursday identified the British-accented militant from the chilling videos as Mohammed Emwazi, a man in his mid-20s who was born in Kuwait and raised in a modest, mixed-income area of west London.
No one answered the door at the brick row house 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.
One man who knew Emwazi portrayed him as compassionate, a description completely at odds with the cruelty attributed to him.
"The Mohammed that I knew was extremely kind, extremely gentle, extremely soft-spoken, was the most humble young person that I knew," said Asim Qureshi of CAGE, a London-based advocacy group which works with Muslims in conflict with British intelligence services
Qureshi said he met Emwazi in 2009, but hadn't had contact with him since January 2012.
Qureshi said he saw strong similarities between the man in a beheading video and Emwazi.
But he said "I can't be 100 percent certain."
"The guy's got a hood on his head. It's very, very difficult," Qureshi said.
British anti-terror officials wouldn't confirm the man's identity, citing a "live counterterrorism investigation." National Security Council spokeswoman Bernadette Meehan said the U.S. couldn't confirm or deny the identity, either.
Asked whether it was helpful or hurtful to have the jihadi publicly identified, White House Press Secretary Josh Earnest said investigators over the last several months "have found it to their advantage to not talk publicly about the details or progress of that investigation." He didn't confirm the identity of the suspect.
The Center for the Study of Radicalization and Political Violence at King's College London, which closely tracks fighters in Syria, said it believed the identification was correct.
"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 was known to Britain's intelligence services before he traveled to Syria in 2012, and Qureshi said he had accused British spies of harassing him.
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, who suspected him of attempting to join al-Shabaab militants in Somalia.