The number of Guantanamo detainees participating in a hunger strike has risen to 100 out of 166, a spokesman for the US-run military prison said Saturday.
Among those refusing sustenance, 20 have been given nasal feeding tubes, Lieutenant Colonel Samuel House said in a statement. Five have been hospitalized but are not in life-threatening condition.
The rapidly growing protest movement began on February 6, when inmates claimed prison officials searched Korans in a way they considered blasphemous, according to their lawyers. Officials have denied any mishandling of Islam's holy book.
The strike, in its third month, has now turned into a larger protest by prisoners against their indefinite incarceration without charge or trial over the past 11 years.
On Friday, the White House said it continues to closely monitor the hunger strikers and that President Barack Obama remained "committed to closing" Guantanamo.
"Some progress had been made under this administration and under the previous administration," White House spokesman Jay Carney said.
He added that "a fundamental obstacle to closing this detention facility ... remains in Congress."
Lawyers for the detainees say the official numbers are too low and that around 130 inmates are observing the hunger strike.