A record number of inmates at Guantanamo Bay are on a hunger strike which started in February, protesting long-term incarceration without trial.
A military spokesman said that around 77 inmates are denying food, resulting in many being force-fed through tubes.
Five of them have been admitted to hospitals, but none are facing life-threatening conditions.
Lawyers representing the inmates say the number is much higher than 77, saying it is hovering around 100. That would make up more than half of the 166 prisoners.
"Hunger strike figures have been climbing since U.S. troops raised a communal medium-security compound at the prison camps April 13, and placed about 65 captives under single-cell lockdown," Carol Rosenberg of the Miami Herald said. "Weeks before, the detainees had covered up most of the prison's surveillance cameras and kept themselves largely out of view of their U.S. Army guards, the military said, stirring fears that some were planning to commit suicide."
Some inmates have done interviews with media outlets about their starvation. Shaker Amer, who has been held at the camp for 11 years with no charges, wrote about how he denied food for nearly 70 days.
Amer said, "More than a decade of my life has been stolen from me, for no good reason. I resent that; of course I do. I have missed the birth of my youngest son, and some of the most wonderful years with all my four children."
"If I have to die here, I want my children to know that I died for a principle, without bowing to my abusers. I have been on hunger strike for more than 60 days now. I have lost nearly a quarter of my body weight. I barely notice all of my medical ailments any more - the back pain from the beatings I have taken, the rheumatism from the frigid air conditioning."
"Today I am on my 68th day. But a man in my block has been on strike since 2005."