HONOLULU — A suspected leader ofAl Qaeda who was to go on trial in New York this month in the 1998 bombings of two American Embassies in East Africa died in government custody on Friday night after complications from longstanding medical problems, federal prosecutors said.
The man, Nazih Abdul-Hamed al-Ruqai, also known as Abu Anas al-Libi, had liver cancer. On Wednesday, he was taken to a hospital in New York from the Metropolitan Correctional Center, where he had been held since shortly after American commandoscaptured him in Libya in October 2013.
“We write now to inform the court that despite the care provided at the hospital, his condition deteriorated rapidly,” the United States attorney for the Southern District of New York,Preet Bharara, said in a letter to the judge overseeing the case.
Mr. Bharara said that federal marshals had been in regular contact with Mr. Ruqai’s lawyer, who he said was with Mr. Ruqai throughout the day Friday, as was an imam.
Mr. Ruqai, 50, had a $5 million bounty on his head until his capture in Tripoli, the Libyan capital, ended a 15-year manhunt. He was taken peacefully into custody and interrogated before being moved to New York to stand trial.
According to an indictment filed in 2000 by prosecutors in New York, Mr. Ruqai helped conduct “visual and photographic surveillance” of the United States Embassy in Nairobi, Kenya, in 1993 and again in 1995. The August 1998 bombing of that embassy killed more than 200 people, including 12 Americans. Ten Tanzanians died in the attack on the embassy in their country on the same morning.
The authorities said that Mr. Ruqai had spoken with other Qaeda leaders about attacking American targets in retaliation for the United States peacekeeping operation in Somalia.
Mr. Ruqai, who was born in Tripoli, joined Al Qaeda in the early 1990s, when it was based in Sudan and led by Osama bin Laden. Several years later, he moved to Britain, claiming political asylum as a Libyan dissident.
It is not clear how he ended up in Libya in 2013. But after the fall of Col. Muammar el-Qaddafi’s government in 2011, Libya became a haven for militants, who could move easily throughout the country. Although Mr. Ruqai was thought to have been in Libya on Sept. 11, 2012, when militants attacked two American outposts in Benghazi — killing the United States ambassador, J. Christopher Stevens, and three other people — he was not believed to have played a role in those attacks.
Coming two years after Bin Laden was killed by American commandos in Pakistan, the capture of Mr. Ruqai was the latest blow to the remnants of Al Qaeda, whose leadership has been largely decimated.