ISIS, which controlled swathes of Syria and Iraq at the peak of its power from 2014 to 2017, beheaded numerous people in captivity, including Western hostages, and released videos of the killings.
Qatar’s international search and rescue group began the search on Wednesday, accompanied by several Americans, the sources said. The group, deployed by Doha to earthquake zones in Morocco and Turkey in recent years, had so far found the remains of three bodies, the sources added.
One of the sources — a Syrian security source — stated the remains had yet to be identified. The second source noted it was unclear how long the mission would last.
The Qatari mission gets under way as US President Donald Trump prepares to visit Doha and other Persian Gulf Arab allies next week and as Syria’s ruling parties, close allies of Qatar, seek relief from US sanctions.
The Syrian source said the mission’s initial focus was on looking for the body of aid worker Peter Kassig, who was beheaded by ISIS in 2014 in Dabiq in northern Syria. The second source added Kassig’s remains were among those they hoped to find.
US journalists James Foley and Steven Sotloff were among other Western hostages killed by ISIS. Their deaths were confirmed in 2014.
US aid worker Kayla Mueller was also killed in ISIS captivity. She was raped repeatedly by ISIS leader Abu Bakr al-Baghdadi before her death, US officials have said. Her death was confirmed in 2015.
“We’re grateful for anyone taking on this task and risking their lives in some circumstances to try and find the bodies of Jim and the other hostages,” said Diane Foley, James Foley’s mother.
“We thank all those involved in this effort,” Foley added.
The families of the other hostages, contacted via the Committee to Protect Journalists, did not immediately respond to a request for comment.
The extremists were eventually driven out of their self-declared caliphate by a US-led coalition and other forces.
Plans for the Qatari mission were discussed during a visit to Washington in April by Qatari Prime Minister Sheikh Mohammed bin Abdulrahman al-Thani and the minister of state for the foreign ministry, Mohammed al-Khulaifi — a trip also designed to prepare for Trump’s visit to Qatar, one of the sources said.
Another person familiar with the issue said there had been a longstanding commitment by successive US administrations to find the remains of the murdered Americans, and that there had been multiple previous “efforts with US government officials on the ground in Syria to search very specific areas.”
The person did not elaborate. But the US has had hundreds of troops deployed in northeastern Syria that have continued pursuing the remnants of ISIS.
The person added the remains of Kassig, Sotloff and Foley were most likely in the same general area, and that Dabiq had been one of ISIS’s centerpieces — a reference to its propaganda value as a place named in an Islamic prophecy.
Mueller’s case differed in that she was in al-Baghdadi’s custody, the person continued.
Two ISIS members, both former British citizens who were part of a cell that beheaded American hostages, are serving life prison sentences in the US.
Syrian interim President Ahmed al-Sharaa, who seized power from Bashar al-Assad in December, battled ISIS when he was the commander of another faction — the al-Qaeda–linked Nusra Front — during the Syrian war.
Al-Sharaa severed ties to al-Qaeda in 2016.
