Updated at 11:20 a.m. ET

Abu Anas al-Libi, the man who allegedly planned the 1998 attack on U.S. embassy buildings in East Africa and was awaiting trial in America, has died of complications from liver surgery, the Justice Department confirms.

Al-Libi, believed to have been an al-Qaida operative, was captured by U.S. special forces in the Libyan capital in Oct. 2013 and brought to the U.S. to stand trial.

In a letter sent to U.S. District Judge Lewis Kaplan dated Jan. 3, U.S. Attorney Preet Bharara informed the court on Dec. 31, al-Libi was taken from his prison cell at Metropolitan Correctional Center to an area hospital. Bharara wrote "that despite the care provided at the hospital, his condition deteriorated rapidly, and al-Liby passed away yesterday evening."

As NPR's Leila Fadel reports from Cairo, "Abu Anas al-Libi, whose real name is Nazih Abdul-Hamed al-Ruqai, was indicted more than a decade ago in a U.S. federal court for involvement in twin bombings of U.S. embassies in Tanzania and Kenya. The attacks killed more than 224 people."

The Associated Press reports that on Saturday, al-Libi's wife, who asked to be identified as Um Abdullah, told the news agency that the experience of being in U.S. custody had exacerbated her husband's ailments, including hepatitis C, and hastened his death. He was 50.

"I accuse the American government of kidnapping, mistreating, and killing an innocent man. He did nothing," she said, according to the AP.

Um Abdullah was informed of her husband's death by the U.S. embassy in Libya, she said.

The Telegraph reports that after spending a week aboard a U.S. Navy ship in the Mediterranean where he was interrogated, in his first appearance in a U.S. court in October 2013, al-Libi "appeared frail and exhausted as he shuffled into the courtroom with his hands cuffed behind his back."

He pleaded not guilty to charges of conspiracy to murder, kidnap and maim Americans and to damage U.S. buildings and property, including U.S. national defense facilities. He was denied bail.

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