The number of detainees taking part in a hunger strike at the US-run Guantanamo Bay military prison has grown to 77, an increase of 25 in just the past few days, according to a US military spokesman.

Lieutenant Colonel Samuel House said in a statement that of the detainees refusing food, 17 are receiving "enteral feedings," a process involving being force-fed via tubes.

Five of the inmates have been admitted to hospital, although none faces "life-threatening conditions," House said.

The facility, which houses 166 detainees, has been hit by hunger strikes since February 6, when inmates claimed prison officials searched their Qurans for contraband. Officials have denied any mishandling of Islam's holy book.

The hunger strikers are protesting against their incarceration without charge or trial at Guantanamo over the past 11 years.

"They say they want their freedom," Al Jazeera's Rosiland Jordan, reporting from Washington, said. "Or they'll die trying to get it."

Lawyers representing inmates at the prison have said most of the estimated 130 detainees at Guantanamo's Camp Six wing, which houses "low-value" prisoners, are on hunger strike.

Torture

Al Jazeera journalist Sami al-Haj, who spent six years at the Guantanamo Bay prison, said: "They used dogs on us, they beat me, sometimes they hung me from the ceiling and didn't allow me to sleep for six days."

Brandon Neely, a US Military Policeman and former Guantanamo guard, told Al Jazeera that detainees were "treated horribly".

Neely said he regularly watched detainees being beaten and humiliated, as well as watching a medic beat an inmate.

Bill O'Neil, an international lawyer, pointed out that by its actions in Guantanamo, the US has violated the UN Convention against Torture, which it has ratified and is thus legally bound to uphold.

"As such under international law binding on the US, those involved in planning, ordering and overseeing those acts in Abu Ghraib, Guantanamo and elsewhere that constituted torture [and those subordinate officers who were ordered to commit torture cannot use the defence of "following superior orders"] should be investigated and if the evidence so indicates, prosecuted," O'Neil told Al Jazeera.

Despite an order in 2011 by Barack Obama, the US president, to close Guantanamo down by the end of that year, there are no current plans to shut the prison.