Former Guantanamo Bay detainee Moazzam Begg said in an exclusive interview with ABC News that his American captors were responsible for the torture and deaths of two detainees.
Begg, who was recently freed after nearly three years in captivity, said the deaths occurred at Bagram Airbase in Afghanistan, where he was held before being transported to Guantanamo Bay Detention Center in February 2003.
U.S. officials said that two detainees died in U.S. custody at the time and that 28 soldiers have been implicated in incidents at Bagram.
The British-born Begg was arrested after raising the suspicions of U.S. officials by making several trips to training camps in Afghanistan and moving to the country with his wife and children just three months before the terrorist attacks of 9/11.
He was arrested three months later and taken to a U.S. detention center at Kandahar Air Base in Afghanistan.
"They left me there tied up with my hands tied behind my back, hog tied, with a hood over my head and kicked and punched me several times," Begg told ABC News.
Begg said he was later transferred from Kandahar to Bagram. He sketched the facility, showing his cell -- No. 6 -- and the others nearby. In June 2002, according to Begg, word spread that the detainee in cell No. 3 tried to escape.
"Shortly after that, I saw two guards I had been friendly with -- one in particular -- who dragged the body of this limp detainee across the medical room," Begg said. "And within half an hour or so they carried out a stretcher with a body that was covered -- its face was covered. From that, I assumed the person had been killed.
Begg said one of the guards later told him what happened.
"He told me what had happened and how, he himself, how viciously he beat this person because of sheer anger that he felt this person actually tried to escape," Begg said.
Army investigators later asked Begg about that June incident. But, Begg says, they seemed far more interested in what he said he witnessed six months later when he was in cell No. 1, while another prisoner was in the air lock just outside the cell.
"A lot of the period, he was actually suspended with his hands tied above his head with the shackles to the ceiling area with a hood placed over his head," said Begg.
Begg said the prisoner shouted for help and went limp, and "because he wouldn't stand, they started punching him in the kidneys."
That was the last time Begg says he saw the inmate. He and other detainees suspected the worst, he said, "because there were several soldiers running around as if they were really worried about something."
Begg, who was never charged with a crime, was released in January and is now living in Britain.
The Pentagon has been investigating the two deaths at Bagram. Last week, a military policeman, who pleaded guilty to assault and making false statements, was sentenced to three months in prison.
ABC News' Martha Raddatz filed this report for "World News Tonight."