Two prisoners have been convicted at Guantanamo, including Hamdan, who was the first to undergo a complete trial, and David Hicks, an Australian.

Hicks avoided trial by admitting he trained with al-Qaeda in Afghanistan and pleading guilty in March 2007 to providing material support for terrorism.

He finished his nine-month sentence in Australia in December 2007.

Facing trial

The most high-profile trials due to take place are those involving the alleged planners of the September 11, 2001, attacks on New York and Washington in which 3,000 people were killed.

 Khalid Sheikh Mohammed, centre, and Waleed bin Attash,  are to face trial [AFP]

Khalid Sheikh Mohammed, al-Qaeda's suspected third-in-command, is among five defendants set to face trial over the attacks.

Mohammed and Ali Abdul Aziz Ali, Ramzi bin al-Shibh, Mustafa Ahmed al-Hawsawi and Walid bin Attash are charged with conspiring with al-Qaeda to murder civilians in the attacks.

No trial date has been set but all could face execution if they are convicted.

Abd al-Rahim al-Nashiri is accused of planning the attack on the warship USS Cole in 2000 that killed 17 US sailors and would face execution if convicted on charges that include murder and terrorism.

A Saudi Arabian national of Yemeni descent, al-Nashiri is accused of being al-Qaeda's operations chief for the Arabian peninsula.

Ahmed Khalfan Ghailani, a Tanzanian citizen, could also face execution if convicted of charges he helped plan and prepare a truck bomb that killed 11 people and wounded at least 85 at the US embassy in Tanzania in 1998.

Mohammed Jawad, a 23-year old from Afghanistan, has been in Guantanamo prison since he was 16 or 17.

He is accused of throwing a grenade into a US military vehicle in December 2002 in Afghanistan, wounding three people, including two US soldiers.

Prisoner suicides

The US holds about 265 prisoners at Guantanamo and has released or transferred to other governments more than 500 previously held there.

Four Guantanamo prisoners have committed suicide by hanging, three in June 2006 and one in May 2007.

The deaths remain under investigation by the Navy Criminal Investigative Service.

A fifth prisoner died of cancer in December 2007, the first to die of natural causes.