British and American intelligence services have identified the man suspected of beheading US journalist James Foley as a UK citizen who traveled to Syria to join the Islamic State, the Sunday Times reported.

Government sources said the masked man seen in a video of Foley’s death is known as “Jihadi John” among Islamic State fighters. In the video, released by IS last week, a man with a London accent can be seen brandishing a knife while standing next to a kneeling Foley before beheading him. The gruesome clip ended with footage of Foley’s decapitated body lying on the ground.

Although sources did not officially confirm the identity of the masked man, the Sunday Times reported (paywall) that a London-based rapper, Abdel-Majed Abdel Bary, 23, is a key suspect in the case.

Bary, whose songs have featured on BBC radio in the past, last year left his family’s house in Maida Vale west London. He lived with his mother and five siblings in what was described as a “£1 million home.”

UK Foreign Secretary Philip Hammond was quoted by the Sunday Times as saying that Islamic State is “turning a swath of Iraq and Syria into a terrorist state as a base for launching attacks on the West.”

Hammond added that “sooner or later they will seek to strike us on British soil.”

Speaking of Foley’s executioner, Hammond said that “it is horrifying to think that the perpetrator of this heinous act could have been brought up in Britain.”

Foley’s death “is a reminder to us all that Islamic extremism in Iraq and Syria is not only causing huge suffering in those countries but is also a barbaric ideology threatening us at home,” he said.

American journalist James Foley, kneeling in orange, in a video released by the Islamic State, which apparently showed him being beheaded by his captor, August 19, 2014. (screen capture: YouTube/News of the World)

American journalist James Foley, kneeling in orange, in a video released by the Islamic State, which apparently showed him being beheaded by his captor, August 19, 2014. (screen capture: YouTube/News of the World)

According to The Independent, Bary went under the pseudonyms “L Jinny” or “Lyricist Jinn” when he was involved in the London rap scene.

Bary’s father, Egyptian national Adel Abdul Bary, was believed to be a close confidant of Osama bin Laden and was extradited from the UK to the US in 2012 for his alleged involvement in the 1998 bombings of two US embassies in east Africa.

Earlier this year Bary the son tweeted a picture of himself from Syria holding a severed head, with the message “Chillin’ with my homie or what’s left of him.” The pictures was apparently taken in Raqqa, a key position seized by the Islamic State as carved out large swaths of Iraq and Syria for its self-declared Islamic caliphate.

Bary’s rap lyrics, which in the past focused on drug abuse and violence, seemed to become increasingly hostile to authorities after the extradition of his father.

In his most recent video clip, posted to YouTube in March this year, he talked of his anger at his father’s 1998 arrest.

“Give me the pride and the honor like my father, I swear the day they came and took my dad, I could have killed a cop or two,” he rapped. “Imagine then I was only six, picture what I’d do now with a loaded stick. Like boom bang fine, I’m wishing you were dead, violate my brothers and I’m filling you with lead.”

Foley’s slaying has raised fears for the fate of Steven Sotloff, another US hostage held by IS who was seen in the same video. The masked man in the video threatened Sotloff’s life if US airstrikes on IS continue. Earlier this month the US began airstrikes to help Iraqi and Kurdish forces halt the IS sweeping advances.

The Sunday Times reported that US President Barack Obama had deliberated for several weeks on whether to approve a rescue mission by US commandos earlier this year aimed at rescuing the hostages. The mission eventually went ahead but when the special forces reached the location where the hostages were believed to be held they were no longer there.