BBC NEWS | Americas | Profile: Key 9/11 suspects

US President Barack Obama is seeking the suspension of all military tribunals at the Guantanamo Bay detention camp.

The request, if granted, could halt a number of cases including those of five men held for their alleged involvement in the 11 September 2001 attacks in the US.

The following profiles and what is known of the charges against the suspects are compiled from BBC and news agency reports and information released by the Pentagon and US intelligence officials.

KHALID SHEIKH MOHAMMED

Khalid Sheikh Mohammed - described by US intelligence as "one of history's most infamous terrorists" - has admitted being responsible "from A to Z" for the 11 September 2001 attacks on the United States, according to the Pentagon.

He also confessed to a role in 30 plots other than 9/11 including planned attacks on Big Ben and Heathrow airport in London and the beheading of US reporter Daniel Pearl in Pakistan in 2002, according to a transcript of his hearing at Guantanamo Bay.

He was believed to be the number three al-Qaeda leader before his capture in a safe house in Pakistan in March 2003. He was held in US custody at an undisclosed location from then until his transfer to Guantanamo Bay in 2006.

At a pre-trial hearing at Guantanamo Bay in December 2008, Mr Mohammed said he wanted to plead guilty to all charges against him.

He claims to have been tortured while in American custody and has requested the dismissal of his US lawyers.

Born in Kuwait of Pakistani extraction, Khalid Sheikh Mohammed claims to have joined the Muslim Brotherhood at the age of 16.

After graduating from college in the US, he went to Afghanistan to participate in the anti-Soviet jihad. It was there that he is believed first to have met Osama Bin Laden.

He went to the Philippines and was implicated in the plot to blow up US airliners over the Pacific in 1995, known as Operation Bojinka.

CHARGES Conspiracy. Murder in violation of the law of war, attacking civilians, attacking civilian objects, intentionally causing serious bodily injury, destruction of property in violation of the law of war, terrorism and providing material support for terrorism Hijacking or hazarding a vessel

He features prominently in the US 9/11 Commission Report on how the 11 September 2001 attacks were carried out. His testimony was also used by defence lawyers for Zacarias Moussaoui, jailed for life in 2006 for his role in the plot.

Khalid Sheikh Mohammed helped build close operational ties between al-Qaeda and the shadowy militant group Jemaah Islamiah (JI) in south-east Asia, according to US intelligence.

By late 2001 he had become external operations chief for al-Qaeda and was involved in plots targeting Britain and the US, the Pentagon says.

Former Pakistani President Pervez Musharraf has alleged that he also helped lay the groundwork for the 7 July 2005 bombings in London.

RAMZI BINALSHIBH

In his combatant status review at Guantanamo Bay, the US cited evidence describing Ramzi Binalshibh as the co-ordinator of the 9/11 attacks.

He is said to have become a key member of the al-Qaeda cell in Hamburg, Germany, after seeking asylum there in the late 1990s and becoming a student.

According to US officials, he met Mohammed Atta, the leader of the Hamburg cell, and two other hijackers, Marwan al-Shehhi and Ziad Jarrah, in 1997. Two years later, the four travelled to Afghanistan where they met Bin Laden.

Mr Binalshibh was intended to be one of the hijackers but was unable to get a US visa, intelligence officials say.

CHARGES Conspiracy. Murder in violation of the law of war, attacking civilians, attacking civilian objects, intentionally causing serious bodily injury, destruction of property in violation of the law of war, terrorism and providing material support for terrorism Hijacking or hazarding a vessel

Instead, he reportedly assisted the 11 September attacks by relaying orders from al-Qaeda's leadership in Afghanistan and Pakistan to operatives in the US and Germany, as well as organising travel and money transfers.

US intelligence says he left Germany a week before the attacks and made his way to Afghanistan and then to Pakistan, where he worked with Sheikh Mohammed on plots against Western targets, including plans to crash aircraft into Heathrow airport in the UK.

He was interviewed by an al-Jazeera reporter in 2002, during which he showed souvenirs of the 9/11 planning, including a flight instruction book signed by lead hijacker Mohammed Atta.

He was captured in Pakistan in September 2002.

The US described him at his combatant status review as "uncooperative and unresponsive", vowing to have nothing to do with the process.

A pre-trial hearing was held at Guantanamo Bay in January 2009 to determine whether Mr Binalshibh was mentally competent to represent himself.

Amid chaotic scenes, he told the court in Arabic that he was "proud" of the 9/11 attacks.

MUSTAFA AHMAD AL-HAWSAWI

A Saudi said by US intelligence officials to be one of two key financial people used by Khalid Sheikh Mohammed to arrange the funding for the 11 September hijackings.

CHARGES Conspiracy. Murder in violation of the law of war, attacking civilians, attacking civilian objects, intentionally causing serious bodily injury, destruction of property in violation of the law of war, terrorism and providing material support for terrorism

He is suspected of meeting many senior al-Qaeda figures, including Bin Laden, soon after the attacks. Financial links have been found between Mr Hawsawi, other terror suspects and some of the hijackers, US intelligence says, and he helped arrange travel for some of them.

Testimony from Mr Hawsawi was used in the trial of Zacarias Moussaoui, saying he had seen him in an al-Qaeda guesthouse in early 2001 but was never involved with him.

He was captured in Pakistan in 2003.

ALI ABD AL-AZIZ ALI

Also known as Ammar al-Baluchi, he is accused of serving as a key lieutenant to Khalid Sheikh Mohammed - his uncle - during the 11 September operation.

CHARGES Conspiracy. Murder in violation of the law of war, attacking civilians, attacking civilian objects, intentionally causing serious bodily injury, destruction of property in violation of the law of war, terrorism and providing material support for terrorism Hijacking or hazarding a vessel

Born in Balochistan and raised in Kuwait, his chief mentor was his cousin, Ramzi Yousef, jailed in the US for masterminding the 1993 bombing of the World Trade Center.

US intelligence officials say he delivered funds to the 11 September hijackers and later helped Sheikh Mohammed communicate with "shoe bomber" Richard Reid and other plotters, including Majid Khan.

Following his uncle's arrest, he is said to have assumed responsibility for planning hijacking attacks from Heathrow airport and bombings against Western targets in Karachi in 2003.

He was within days of completing preparations for the Karachi plot when captured, the US says.

WALID BIN ATTASH

Yemeni national Walid Bin Attash has admitted masterminding the bombing of the American destroyer, USS Cole, in Yemen in 2000, which killed 17 sailors, according to the Pentagon.

CHARGES Conspiracy. Murder in violation of the law of war, attacking civilians, attacking civilian objects, intentionally causing serious bodily injury, destruction of property in violation of the law of war, terrorism and providing material support for terrorism Hijacking or hazarding a vessel

Mr Bin Attash also said he helped plan the 1998 bomb attacks on the US embassies in Kenya and Tanzania that killed 213 people, according to a transcript of his hearing at Guantanamo Bay.

Mr Bin Attash, also known as Tawfiq Bin Attash and Khallad, was a key al-Qaeda operative from 1998 until his capture in 2003, according to the US.

He is also accused of involvement in the 11 September 2001 attacks and met two of the hijackers, Nawaf al-Hamzi and Khalid al-Midhar, to help them check out US flights in Asia.

He was allegedly picked as one of the hijackers himself but was prevented from taking part when he was briefly arrested in Yemen earlier that year. He is said to have served as Bin Laden's bodyguard.

US intelligence officials say he was planning an attack on the US consulate in Karachi with fellow suspect Ali Abd al-Aziz Ali when he was captured in a raid in the city. They believe he was also involved in a plot against Heathrow airport.

A sixth man, Mohammad al-Qahtani, had been charged with murder and war crimes but the charges were dropped on 13 May 2008.

Mr Qahtani was alleged to have been the planned 20th hijacker.