GUANTÁNAMO BAY, Cuba, Dec. 4  A detainee at the military detention camp here cut his throat with his own fingernail, causing substantial blood loss early last month, but was not at risk of death, military officials said today.

“He did in fact use a sharpened fingernail,” Cmdr. Andrew Haynes, the deputy commander of the guard force here, told reporters during a camp tour.

Commander Haynes said there had been four to six incidents of detainees harming themselves in the last two months, a rate that he said was consistent with recent experience. Those incidents showed that a potentially deadly struggle between detainees and their jailers continues, largely out of public view here. A detainee committed suicide in May following three others the previous June. There have also been numerous suicide attempts.

Advocates for detainees describe such acts as signs of desperation borne of indefinite detention and hopelessness. But camp administrators label them a tactic to draw publicity and provoke criticism of the United States government.