Activists demanding the closure of Guantanamo prison marked the 100th day of a hunger strike there Friday by submitting a petition to the White House containing some 370,000 signatures.

A group of activists wearing orange jumpsuits and black hoods like those used on detainees at Guantanamo Bay gathered outside the White House to call for the immediate closure of the controversial jail.

Free them or put them on trial. Thus urges a petition to President Barack Obama over the prisoners held at Guantanamo, jailed and in limbo for more than a decade.

The petition launched by Guantanamo's former chief military prosecutor Colonel Morris Davis was signed by more than 145,500 people by Monday for the president to bring some kind of closure to the fate of the terror suspects at the U.S. prison on the eastern tip of Cuba.

Cuba's foreign minister demanded Wednesday that Washington shut its controversial jail at Guantanamo Bay and return the long-held military base to Havana.

The comments by Bruno Rodriguez Parrilla to the U.N. Human Rights Council in Geneva came a day after U.S. President Barack Obama vowed again to shut the military prison, saying it was damaging U.S. interests.

Extra medical staff have been sent to the U.S. military prison in Guantanamo Bay, Cuba amid a hunger strike that has spread to nearly two-thirds of the detainees, authorities said Monday.

Some 40 U.S. Navy medical personnel, including nurses and specialists, arrived over the weekend at the U.S. base in Cuba, Lieutenant Colonel Samuel House, a military spokesman at Guantanamo said.

More Guantanamo detainees have joined a growing hunger strike at the reviled U.S. military prison, with nearly a third of the 166 war-on-terror suspects participating, a spokesman said.

Captain Robert Durand said that 52 detainees are refusing food, 15 of whom are being tube-fed by prison officials. That was up from 43 hunger strikers, including 11 receiving enteral feeds, on Friday.

The self-proclaimed mastermind of the September 11 attacks and his four co-defendants are due back in Guantanamo court Monday for hearings to pave the way to their trial.

It will mark the second appearance for Khalid Sheikh Mohammed and the other alleged co-plotters before the special tribunal known as military commissions on the U.S. naval base. They face the death penalty if convicted for the 2001 attacks on the United States that left nearly 3,000 people dead.

Pakistani national Majid Khan pleaded guilty Wednesday at a Guantanamo military tribunal in a landmark case that could speed the trials of September 11 suspects.

Khan, 32, a protégé of September 11 mastermind Khalid Sheikh Mohammed, pleaded guilty to conspiracy, murder and attempted murder in violation of the laws of war, and to material support for terrorism and espionage.