Two British extremists believed to have been members of so-called Islamic State's brutal executions group dubbed "The Beatles" have reportedly been captured.
Alexanda Kotey and El Shafee Elsheikh were detained by US-allied Kurdish militia fighters in January, the New York Times said.
Along with Mohammed Emwazi - the killer nicknamed Jihadi John - and Aine Davis, they are believed to have been part of a group named after the 60s band because of their English accents.
The four Londoners were linked to a string of hostage murders in Iraq and Syria during the bloody Islamist uprising.
Unnamed US officials told the New York Times that Kotey, 34, and Elsheikh, 29, were captured by the Kurdish-led Syrian Democratic Forces, which were fighting the last remaining pockets of IS fighters near the river Euphrates on the Iraq/Syria border.
It added that the men were identified by fingerprints and other biometric means.
Former child refugee Elsheikh was a mechanic from White City in west London, and Kotey was from Paddington.
In January 2017, US authorities named Kotey as a member of the cell and said they had imposed sanctions on him.
In a statement at the time, the US State Department said Kotey was "one of four members of an execution cell for... the Islamic State of Iraq and the Levant (Isil)".
It went on: "The notorious cell, dubbed 'The Beatles' and once headed by now-deceased Mohamed Emwazi (also known as Jihadi John), is responsible for holding captive and beheading approximately two dozen hostages, including several Westerners. Among them: American journalists James Foley and Steven Sotloff, and American aid worker Peter Kassig.
"As a guard for the cell, Kotey likely engaged in the group's executions and exceptionally cruel torture methods, including electronic shock and waterboarding.
"Kotey has also acted as an Isil recruiter and is responsible for recruiting several UK nationals to join the terrorist organisation."
Elsheikh, it said, "was said to have earned a reputation for waterboarding, mock executions, and crucifixions while serving as an Isis jailer".
Emwazi, who was killed in a US air strike in 2015, appeared in a number of videos in which captives including British aid workers David Haines and Alan Henning were beheaded.
The fourth member, Davis, was convicted of being a member of a terrorist organisation and jailed for seven-and-a-half years at a court in Silivri, Turkey, in May 2017.
The Foreign Office said it did not comment on individual cases or ongoing investigations.