(ALEXANDRIA, Va.) — A federal jury found ISIS fighter El Shafee Elsheikh guilty on all counts of being part of a core group of British terrorists known as the “Beatles,” who held hostage 26 westerners in a conspiracy that led to the murders of four Americans and at least two Britons.

The jury deliberated for less than a full day. Closing arguments came Wednesday and they were handed the case in the afternoon. By the time they finished lunch Thursday, they had reached a verdict.

“Elsheikh really incriminated himself,” despite wearing a mask as he and the other Britons brutalized her son, said Diane Foley, mother of New Hampshire-raised journalist James W. Foley.

Humanitarian aid worker Kayla Mueller’s dad Carl said justice was served, and added that he felt his daughter’s presence throughout the trial.

“This is what the families asked for. And this is what we got. It’s the American justice system at work at its best,” he told ABC News.

As the jury settled in for its short deliberations, Mueller approached Elsheikh’s defense team, thanking them for their service as court-appointed lawyers and assuring them of his respect. Some of the defense team wiped away tears. “I hold no malice toward them for what they do,” he said.

Many of the former hostages testified in graphic detail about the beatings and other cruelties inflicted on them, seated a mere 12 feet from the man now convicted of breaking ribs and slapping faces of captives the Beatles starved and tortured.

Because of an agreement with the UK, neither Elsheikh or co-defendant Alexanda Kotey, who pleaded guilty, faced the death penalty.

Elsheikh doesn’t deny fighting for ISIS but rested his defense in U.S. District Court for the Eastern District of Virginia on his claim that this was a case of mistaken identity about holding the westerners captive. He faces a life sentence for the conviction of holding hostages and causing the deaths of journalists and humanitarian aid workers.

In closing arguments Wednesday, federal prosecutors said Elsheikh was one of the men who brutalized American journalists James Foley and Steven Sotloff, as well as aid workers Peter Kassig and Kayla Mueller. The men were shown in ISIS videos in 2014-15 being beheaded by a black-clad and masked ISIS executioner nicknamed “Jihadi John” because hostages had dubbed the men the “Beatles” to discuss them while in captivity.

The videos shocked the world as the executioner — later named as Mohammed Emwazi — demanded the U.S. cease military strikes against ISIS.

Kayla Mueller, 26, of Prescott, Arizona, was reportedly killed by an airstrike by ISIS in February 2015. It was later revealed that she had been taken by ISIS leader Abu Bakr al-Baghdadi and repeatedly abused and raped.

“Elsheikh, without a shadow of a doubt, is an ISIS Beatle,” prosecutor Raj Parekh told the jury.

But defense lawyer Nina Ginsberg countered that the U.S. never presented any hard evidence that the defendant was anything other than a foot soldier in ISIS battling the Syrian Army.

Despite evidence from a parade of former hostages and FBI agents who testified during the trial about what she described as “loathsome, brutal acts,” Ginsberg said the government failed to prove Elsheikh was a captor, and that he was “never identified at this trial by any of the former hostages.”

The U.S. instead relied primarily on Elsheikh’s own statements after his 2018 capture by Syrian Democratic Forces with fellow admitted ISIS Beatle Alexanda Kotey, who has pleaded guilty. They told several journalists, primarily British filmmaker Sean Langan, on video that they held the westerners captive, got family members’ email addresses from hostages such as Mueller, and beat others such as Danish photojournalist Daniel Rye.

Rye testified on Tuesday, revealing agonizing details of how the British ISIS members had stuck him in the ribs 25 times on his 25th birthday, hanged him by his hands and jammed the barrel of an MP5 submachine gun in his mouth.

He described the loyalty of Foley, who once had an opportunity to escape captivity but refused to abandon his comrade, the British journalist John Cantlie, whose whereabouts and survival remain unknown. Notably, Cantlie’s photo was shown to jurors alongside six other hostages known to have been killed.

The captors forced them to sing a version of “Hotel California,” emphasizing the line, “You can never leave” — but that was hardly the worst of their suffering.

Sotloff tried to leave letters for Mueller in a communal toilet, but they were caught and he, Cantlie and Foley were punished severely, he recalled. When he learned after 13 months he had been ransomed and set for release, Rye said Cantlie came to him.

“He wanted me to bring out a message. ‘If you cannot get us released, drop a bomb on this place – kill us,'” Rye said, as family members of hostages in the courtroom held each other.

By the time he and another hostage were told they were being released as the last two Europeans, Rye said the Americans and British hostages knew they were going to be executed. The U.S. began bombing ISIS in August 2014.

The Americans retreated silently to one corner of the small room, the British men in another corner. As he left the room, “I took one last look at my friends, and thought it was the last time I would see them alive,” Rye told the jury.

Prosecutors said all of the hostages who were brutalized and those ultimately murdered showed superhuman courage. They described a year or more of broken ribs, severe blows to the thighs called “dead legs,” stress positions, water deprivation, mock executions – and finally beheadings which, at least, ended their suffering.

“All these people wanted was to do the right thing,” Assistant U.S. Attorney Dennis Fitzpatrick said.

Sotloff’s father, Art, told ABC News that justice has been served.

“I feel like all of them are looking down on us, pattin’ us on the back for doing the right thing,” he said.

Editor’s Note: ABC News investigative reporter James Gordon Meek is the recipient of the James W. Foley Legacy Foundation’s 2022 World Press Freedom Award for reporting on hostage cases since 1993.

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