A US military official said International Red Cross monitors have begun interviewing Taliban and al-Qaeda prisoners sent from Afghanistan to the US Navy base in Guantanamo Bay, Cuba.
A four-person team from the International Committee of the Red Cross (ICRC) arrived at the isolated base on the eastern tip of Cuba late on Thursday to inspect the prison camp and interview each detainee.
Human rights groups accused Washington of treating the 110 prisoners inhumanely after they were brought shackled and blindfolded from Afghanistan aboard military transport planes.
The US has denied the detainees prisoner-of-war status, which would grant them certain rights under the Geneva Convention. But Defense Secretary Donald Rumsfeld said they were being treated humanely and held "in an environment that is a lot more hospitable than the environments we found them in."
Both the ICRC and UN Human Rights Commissioner Ms Mary Robinson have said they consider the captives to be prisoners of war.
Brig Gen Michael Lehnert said the only incident so far occurred on Wednesday, when one detainee became upset and bit a military policeman on the forearm as he was being transferred from one unit to another.
The bite "did not break the skin," Brig Gen Lehnert said, and the prisoner was moved back to his original unit after he settled down.
The prisoners are being locked in cage-like cells measuring 6 feet by 8 feet, with roofs and floors but open chain-link walls, until permanent holding facilities are completed at the camp.