The dispute is clouded by two issues: military authorities define a juvenile as someone younger than 16 years of age, not 18, as do most human rights groups. Further, the ages of the detainees brought to Guantánamo as enemy combatants cannot be determined with certainty, leaving officials to make estimates.

How's this for a callous response?

"They don't come with birth certificates," said Col. Brad K. Blackner, the chief public affairs officer at the detention camp.

More on the young detainee's claims:

The details of M.C.'s accusations are contained in a 17-page account prepared by Mr. Stafford Smith, in which the prisoner said that he was suspended from hooks in the ceiling for hours at a time with his feet barely missing the floor, and that he was beaten during those sessions. M.C. said a special unit known as the Immediate Reaction Force had knocked out one of his teeth and later an interrogator burned him with a cigarette. Mr. Stafford Smith said he saw the missing tooth and the burn scar.

Some of M.C.'s descriptions match accounts given not only by other detainees, but also by former guards and interrogators who have been interviewed by The New York Times.

He describes being shackled close to the floor in an interrogation room for hours with music blaring and lights in his face. He also said he was shown a room with pictures of naked women and adult videos and told he could have access if he cooperated. His description fits the account of former guards who described such a room and said it was nicknamed "the love shack."

The Red Cross has said that it believed three detainees were between 12 and 14. One other juvenile detainee (who was 15 when seized) is Omar Khadr, whose story we related here.