The US military has acknowledged dealing with three Americans who have been arrested on charges of torture at a private jail they ran in the Afghan capital.
The American military has tried to distance itself from the group, led by a former US soldier named Mr Jonathan Idema, insisting they were freelancers working outside the law.
But spokesman Major Jon Siepmann acknowledged that the military had received a detainee from Idema 's group at Bagram Air Base, north of Kabul, on May 3rd.
Maj Siepmann said Mr Idema had appeared "questionable" the moment he presented the detainee, and that suspicion grew when, one month later, the man turned out not to be the top suspect that Mr Idema had described.
"That doesn't mean at the time that we knew Mr Idema 's full track record or other things he was doing out there," Maj Siepmann said. "This was a person who turned in a person who we believed was on our list of terrorists and we accepted him."
Maj Siepmann did not release the detainee's name or say what crimes he was wanted for. He suggested that the military was initially taken in by Mr Idema, who officials say had been posing as a US special forces soldier.
Afghan security forces seized Mr Idema, two other Americans and four Afghans on July 5th after freeing eight prisoners from a makeshift jail in Kabul.
The seven defendants went on trial in Kabul yesterday, charged with hostage-taking and torture.
AP