(ALEXANDRIA, Va.) -- A British man accused of being one of the infamous quartet of ISIS terrorists nicknamed the "Beatles" by prisoners who they beat and executed was faced down in federal court this week by two of their victims' mothers, and one man who survived their brutality.
El Shafee Elsheikh is accused of a direct role in holding hostage four Americans, several Britons, and other captives between 2013 and 2014 at several makeshift prisons in Syria.
At his trial this week in U.S. federal court in Alexandria, Virginia, prosecutors called as witnesses the mothers of two Americans who did not survive as hostages of ISIS, journalist James Foley and humanitarian aid worker Kayla Mueller.
Foley, of Wolfeboro, New Hampshire, was kidnapped in Syria in 2012 along with British journalist John Cantlie, and was held for nearly two years before he was shown beheaded in a gruesome video by the ISIS Beatle dubbed "Jihadi John," whose real name was Mohammed Emwazi.
"Incredible shock, I didn't believe it -- I didn't want to believe it," Foley's mother Diane testified about learning that her son was killed.
Foley's brother Michael testified about the horror of seeing the ISIS video that showed the remains of his brother, a 38-year old a freelance journalist for Global Post and Agence France-Presse, after the killing that stunned the world on Aug. 19, 2014.
Her head tilted up to look at the ceiling rather than at the defendant, Diane Foley spoke in a clear, strong voice about her son, who had previously survived previous captivity by other militants in Libya.
She said when President Barack Obama "announced Jim had been beheaded, it sunk in."
The Foley family subsequently established the James W. Foley Legacy Foundation to assist hostages, their families and war journalists.
On Tuesday, it was Marsha Mueller's turn.
She told of how her 27-year-old daughter Kayla, of Prescott, Arizona, had traveled to the Middle East and to Turkey and Syria, seeking ways to help refugees of the Syrian civil war.
Then on Aug. 4, 2013, after visiting a Doctors Without Borders hospital in Aleppo, Syria, to help her friend Omar Alkhani install satellite internet, Kayla and her colleagues were kidnapped by armed men.
Dressed in a black sweater, Marsha Mueller's voice became stronger with each passing minute as she told of Kayla's love for owls, music and books, and how Kayla had sought to provide aid to women and children refugees in need.
She described exchanging 27 emails with ISIS, in which they demanded the release of convicted terrorist Aafia Siddiqi or 5 million Euros in exchange for Kayla's release. An ABC News investigation in 2015 found that the FBI and Obama White House had blocked the Foleys, Muellers and other families from paying ISIS' ransom demands -- though ransoms paid for European hostages had led to their release.
After U.S. special mission unit Delta Force raided a makeshift prison on Independence Day 2014, but missed rescuing the hostages by only two days because critics said the intelligence was not acted upon swiftly enough by the White House, ISIS sent an angry email about Kayla and threatened they would "put a bullet in her head."
Her mother said they knew nothing about the U.S. raid, and reacted to the message with fear.
"They were going to kill her," she recalled in court.
Marsha Mueller's voice cracked when she read aloud one of three letters Kayla wrote from ISIS prisons, sending "hugs and kisses" to her niece, and signing it, "All my everything, Kayla." The letters were addressed to her parents, her mentor the Rev. Kathleen Day, and her friends Halla and Orouba Barakat, mother-daughter journalists in Turkey who themselves were later murdered in Istanbul in 2017 and were the subject of an ABC News-Reveal investigation.
When Kayla was reported killed on Feb. 6, 2015, ISIS emailed Carl and Marsha Mueller three photos of their lifeless daughter.
"Her face looks like it is smeared with blood, her eyes are partly open, her mouth is slightly open," Kayla's mother told the jury.
The Muellers later learned that Kayla had stood up for and cared for other hostages, for which she had been repeatedly raped by Abu Bakr al-Baghdadi, the ISIS top leader and self-proclaimed "caliph" of all Muslims. Al-Baghdadi was subsequently killed by Delta Force in 2019 in a raid named "Operation Kayla Mueller" in Mueller's honor.
After providing testimony on Tuesday, Marsha Mueller and Diane Foley held each other in comfort, beyond the eyes and ears of the jurors.
Another witness who faced Elsheikh in court was Spanish journalist Marc Marginedas, who was kidnapped in Syria and held with Mueller, Foley, Cantlie and others including American journalist Steven Sotloff, with whom Marginedas became close during their captivity.
Marginedas recounted in horrifying detail how the four "Beatles" -- so named by Cantlie to keep track of their British-accented captors because their real names were unknown -- inflicted savagery upon them.
As Sotloff's parents Arthur and Shirley looked on in the courtroom, Marginedas recalled how the terrorists appeared to take particular joy in beating Sotloff, who was Jewish. Sotloff told Marginedas he believed that the beatings, some of which occurred in front of his fellow captives, had left him with broken ribs.
But the Jewish journalist never revealed his faith to his captors, and simply wore extra clothing to soften the blows.
"He was a very courageous man who didn't complain much," said Marginedas, who testified in the Virginia courtroom only a week after reporting from the front lines in Ukraine.
A decade after he was kidnapped, Cantlie's whereabouts remain unknown, as do the whereabouts of New Zealand nurse Louisa Akavi, who was kidnapped by ISIS in 2013.
Other victims' relatives who appeared in the courtroom were Paula and Ed Kassig, the parents of former U.S. Army Ranger Peter Kassig, an American aid worker who was killed by ISIS in 2014.
Elsheikh, dressed in a collared shirt and khakis, with black-framed glasses and a beard, sat motionless as each family member took the stand, slouching on his left elbow even as prosecutors played video of interviews he had voluntarily given.
In one clip filmed in 2019 in a Syrian prison where Elsheikh and fellow ISIS Beatle Alexanda Kotey were held following their capture, former ABC News contributor Sean Langan asked if Jihadi John, who the CIA later killed in a drone strike, had asked Elsheikh to get the Muellers' contact information from their daughter to negotiate ransom.
"That was the first time I saw Kayla, I took an email from her," he replied.
Elsheikh, who has admitted in media interviews to being an accomplice of ISIS, faces a life sentence if convicted. Prosecutors took the death penalty off the table in a deal with the British government, which opposes capital punishment.
On Tuesday, after the jury was dismissed for lunch and U.S. District Judge T.S. Ellis III had left the courtroom, Kayla Mueller's friend Omar Alkhani delivered an insult in Arabic to Elsheikh while Elsheikh was being led out by a U.S. Marshal.
One day Elsheikh would meet his former ISIS bosses "in hell," Alkhani shouted.
Elsheikh only glanced back at the outburst.