The jury deliberated for four hours before finding El Shafee Elsheikh guilty on all counts. Elsheikh stood motionless and gave no visible reaction as the verdict was read. He now faces up to a life sentence in prison.

In convicting Elsheikh, the jury concluded that he was one of the notorious “Beatles”, Islamic State captors nicknamed for their accents and known for their cruelty — torturing and beating prisoners, forcing them to fight each other until they collapsed and even making them sing cruel song parodies.

© Provided by PA Media British hostage David Haines (Family handout)The guilty finding came even though none of the surviving hostages could identify Elsheikh as one of their captors. Although the Beatles had distinctive accents, they always took great care to hide their faces behind masks and ordered hostages to avoid eye contact or risk a beating.

Prosecutors suggested in opening statements that Elsheikh was the Beatle nicknamed “Ringo”, but only had to prove that Elshiekh was one of the Beatles because testimony showed that all three were major players in the scheme. Prosecutors said there were three: Elsheikh and his friends Alexenda Kotey and Mohammed Emwazi, who all knew each other in Britain before joining the Islamic State.

Britain stripped Kotey and Elsheikh of their UK citizenship.

Elsheikh, who was captured by the Kurdish-led Syrian Defence Forces in 2018, eventually confessed his role in the scheme to interrogators as well as media interviewers, acknowledging that he helped collect email addresses and provided proof of life to the hostages’ families as part of ransom negotiations.

But testimony showed that he and the other Beatles were far more than paper pushers. The surviving hostages, all of whom were European — the American and British hostages were all killed — testified that they dreaded the Beatles’ appearance at the various prisons to which they constantly shuttled and relocated.

During close arguments on Wednesday, first assistant US attorney Raj Parekh told jurors: “The Beatles were the lifeblood of the hostage conspiracy.”

The convictions on all eight counts in US District Court in Alexandria revolved around the deaths of four American hostages: Mr Foley, Steven Sotloff, Peter Kassig and Kayla Mueller.

All but Ms Mueller were executed in videotaped beheadings circulated online. Ms Mueller was forced into slavery and raped multiple times by Islamic State leader Abu Bakr al-Baghdadi before she was killed.