WASHINGTON (AFP) - Detainees at the Guantanamo Bay prison camp have launched a hunger strike to protest interference with their personal effects, including Qurans, their lawyers and prison officials said on Monday.

"My client and other men have reported that most of the detainees in Camp 6 are on strike, except for a small few who are elderly or sick," said Pardiss Kebriaei, a New York lawyer representing Ghaleb Al-Bihani, a Yemeni detainee.

Camp 6 houses the majority of the 166 detainees still incarcerated at Guantanamo - estimated at about 130 men - who usually don't pose any disciplinary problems or are regarded as a particular risk.

High-profile detainees such as Khalid Sheikh Mohamed, the mastermind of the September 11, 2001 attacks on New York and Washington, are held in a different part of the camp.

Robert Durand, director of public affairs for the Joint Task Force Guantanamo, said nine detainees were engaged in hunger strikes, five of whom were being fed through tubes inserted into their stomachs.

However, he indicated that "refusing delivered food does not make a detainee a hunger striker, not eating does.

"Detainees or an entire cell block may refuse to take any of the fresh, hot meals delivered, but we observe them eating from the ample amounts of food they have in the cell block," he added.

According to Kebriaei, her client - on hunger strike for 30 days - has "lost over 20 pounds and has been told by medical personnel that his health is in serious danger as he is also a diabetic."

Twelve lawyers - including Kebriaei of the Centre for Constitutional Rights - have sent a letter to the commander of Guantanamo, Rear Admiral John Smith, to denounce "a matter that appears to be rapidly deteriorating and reaching a potentially critical level." "We have received reports of men coughing blood, being hospitalised, losing consciousness, becoming weak and fatigued," said the letter.