LONDON Amnesty International called on the United States Monday to give prisoners held at a U.S. naval base in Cuba access to lawyers and independent monitors after a new photo showing a shackled prisoner being carried on a stretcher was published.

Noting that the photograph was an official Pentagon picture, the director of research at the International Human Rights Organization said it revived concerns about the fate of the 158 men being held at the base in Guantanamo, Cuba.

"It is absolutely important that as soon as possible they be given access to lawyers and to independent monitors like us," AFP quoted the research director, Claudio Cordone as saying.

The detainees held in a compound known as "Camp X-Ray" come from about 30 countries, with most being Saudi Arabian nationals, according to statements by U.S., Saudi and other government officials.

They are held in open chain-link enclosures measuring 2.5 meters by 2.5 meters (eight feet by eight feet) behind fences topped with barbed wire and patrolled by guards armed with machine guns and grenade launchers.

Cordone expressed Amnesty's concern at "the cages exposed to the elements, the fact that even when they go to a shower they seem to be taken shackled hand and feet when it doesn't seem to be any need for that and the like."

Washington has come under strong criticism abroad, particularly from its European allies, for its attitude toward those captured over the course of the four-month campaign in Afghanistan against the militant Al-Qaeda network and the allied Taleban militia.

The latest photographs were published in the British press over the weekend and shown on television.

Amnesty also asked that the poor conditions under which the approximately 5,000 prisoners still in Afghanistan were being held not be forgotten.

"We call the United States and the international community to work with the current government to make sure that they have their minimum rights respected in detention."