A prisoner at Guantanamo Bay in Cuba has admitted delivering explosives used to blow up the US embassy in Tanzania in 1998, a Pentagon transcript shows.
Mr Ghailani was one of 14 top suspects sent to Guantanamo
Ahmed Khalfan Ghailani said he did not know about the attack beforehand and was sorry for his role, according to the transcript of a US hearing.
He is quoted as apologising to the US and to the victims' families.
Mr Ghailani is one of 14 detainees transferred in September from secret CIA prisons abroad to Guantanamo Bay.
'Misled over attack'
More than 200 people were killed in the simultaneous attacks in August 1998 on the US embassies in Kenya and Tanzania.
Most of the deaths were in Kenya. The attack on the Tanzania embassy killed 11 people and wounded dozens.
According to the transcript of the closed-door hearing at Guantanamo Bay, Mr Ghailani said he delivered the TNT explosive to "Fahad Mohammed" but did not know that they would be used in the Tanzania bombing.
He was first told the TNT was soap for washing horses, then later that it was explosives "for mining diamonds in Somalia" and for a Somali training camp, Mr Ghailani said, according to the transcript.
Kenyan-born Fahid Mohammed Ally Msalam is wanted by the US in connection with the two bombings.
"It was without my knowledge what they were doing, but I helped them," Mr Ghailani is quoted as saying.
"So I apologise to the United States government for what I did. And I'm sorry for what happened to those families who lost, who lost their friends and their beloved ones."
Mr Mohammed is believed to have planned the 9/11 attacks
According to the US transcript, Mr Ghailani admitted visiting an al-Qaeda training camp in Afghanistan after the bombings. But he denied being a member of al-Qaeda.
Mr Ghailani, a Tanzanian, was arrested in Pakistan in July 2004 and handed over to the US at the beginning of 2005.
So far the US military has conducted nine hearings of the 14 suspects, to determine whether they should be declared "enemy combatants" and therefore subject to military trials.
Transcripts have been released for several hearings - including that of Khalid Sheikh Mohammed, the alleged mastermind of the September 2001 attacks on the US and 30 other plots, according to the Pentagon.