Ahmed Khalfan Ghailani, a Tanzanian, faces a staggering 286 criminal counts including murder and conspiring to use weapons of mass destruction during the bombings of two US embassies in Tanzania and Kenya in 1998 which killed 224 people.

Prosecutor Nicholas Lewin said Ghailani was an integral part of Osama bin Laden's world of America-hating militants, and that he helped supervise the construction of the massive truck bomb that rammed into the US embassy in Tanzania's capital Dar-es-Salaam.

"We will prove both of these massacres in East Africa were the work of a single Al-Qaeda cell. And this man, Ahmed Ghailani, was a vital part of that cell," Lewin said as he pointed at Ghailani, who stared straight ahead in the Manhattan courtroom. "He and his accomplices were committed to Al-Qaeda's overriding goal to kill Americans."

Problems with witness

Ghailani, who was arrested in Pakistan in 2004, is the first inmate of the notorious Guantánamo Bay detention facility in Cuba to have been transferred into the US civil justice system. He faces life in prison if convicted.

The Tanzanian was subjected to what the government calls "enhanced interrogation" at secret CIA prisons, which his lawyers have described as torture.

The trial was delayed after the court last week barred the prosecutor's star witness, Hussein Abebe, to testify, with judge Lewis Kaplan saying that the witness' testimony "would be the product of statements made by Ghailani to the CIA under duress." This was a blow to the prosecution as Abebe was described as a "giant" piece in the case against Ghailani.

The prosecution's first witness was John Lange, the Dar-es-Salaam embassy's acting ambassador in 1988, who described escaping the wrecked building and encountering a burned man lying on the ground "in the last gasps of life."

Other government witnesses will include a convicted former al-Qaeda militant who has agreed to testify against Ghailani in hopes of being given a lighter sentence, Lewin said.

Meanwhile, defense lawyer Steve Zissou portrayed Ghailani, a small, youthful-looking Tanzanian in his mid-30s, as an unwitting accessory in the deadly, double-bomb plot concocted by radical, older friends. Ghailani was a "dupe" who "tagged along" and when he helped buy the truck used in the Dar-es-Salaam blast, he had no idea what the purpose was, Zissou said.

'Test case for future trials'

International legal expert Geert-Jan Knoops calls the Ghailani trial an important "test case"
for future civil trials against former Guantánamo suspects.

"This whole trial against Mr. Ghailani will be a very important example for future cases," Knoops said from Amsterdam.

"An estimated 40 to 50 similar cases can be expected in the future," Knoops said, adding that "on the basis of the decisions in the Ghailani case, the prosecution will re-evaluate its position, and maybe it will create a new selection of the cases."

One key trial will be that against Khalid Sheikh Mohammed, the alleged mastermind of the September 11, 2001, terrorist attacks. Knoops pointed out that the case against Mohammed would have "the same problem, namely statements being obtained through torture."

9/11 plotters still in Guantanamo

US President Barack Obama wants eventually to try all Guantanamo inmates in regular courts, including the five alleged plotters of the 9/11 attacks, and to close the secretive military prison.

Shortly after taking office in January 2009, Obama signed an executive order setting a one-year deadline to empty the prison camps that were then holding some 260 detainees. But the January 2010 deadline has yet to be met, with the prison still open and with little apparent progress made toward the goal of shutting the facilities.