Majid Khan, who underwent ‘enhanced interrogation’, says authorities poured ice water on his genitals and hung him naked from a beam for days

The US Central Intelligence Agency used a wider array of sexual abuse and other forms of torture than was disclosed in a Senate report last year, according to a Guantánamo Bay detainee turned government cooperating witness.

Rectal rehydration and broken limbs: the grisliest findings in the CIA torture report Read more

Majid Khan said interrogators poured ice water on his genitals, twice videotaped him naked and repeatedly touched his “private parts” – none of which was described in the Senate report. Interrogators, some of whom smelled of alcohol, also threatened to beat him with a hammer, baseball bats, sticks and leather belts, Khan said.

Khan’s is the first publicly released account from a high-value al-Qaida detainee who experienced the “enhanced interrogation techniques” of President George W Bush’s administration after the September 11, 2001 attacks on the US.

Khan’s account is contained in 27 pages of interview notes his lawyers compiled over the past seven years. The US government cleared the notes for release last month through a formal review process.

Before the Senate report detailed the agency’s interrogation methods last December, CIA officials prohibited detainees and their lawyers from publicly describing interrogation sessions, deeming detainees’ memories of the experience classified.

Khan’s detailed allegations of torture could not be independently confirmed. CIA officials have said they believed Khan repeatedly lied to them during interrogations.

The 35-year-old Khan, a Pakistani citizen who attended high school in Maryland, is awaiting sentencing after pleading guilty in 2012 to conspiracy, material support, murder and spying charges. In exchange for serving as a government witness, Khan will be sentenced to up to 19 years in prison, with the term beginning on the date of his guilty plea.

Khan confessed to delivering $50,000 to al-Qaida operatives in Indonesia. That money was later used to carry out the 2003 truck bombing of a Marriott hotel in Jakarta that killed 11 people and wounded at least 80 others. Khan also confessed to plotting with 9/11 mastermind Khalid Sheikh Mohammed to poison water supplies, blow up gas stations and serve as a “sleeper agent” for al-Qaida in the United States.

Khan was captured in Pakistan and held at an unidentified CIA “black site” from 2003 to 2006, according to the Senate report. Khan’s lawyers declined to comment on where he was captured or held, which they said remained classified.

In the interviews with his lawyers, Khan described a carnival-like atmosphere of abuse when he arrived at the CIA detention facility.

“I wished they had killed me,” Khan told his lawyers. He said that he experienced excruciating pain when hung naked from poles and that guards repeatedly held his head under ice water.

“‘Son, we are going to take care of you,’” Khan said his interrogators told him. “‘We are going to send you to a place you cannot imagine.’”

Current and former CIA officials declined to comment on Khan’s account.

Khan’s description of his experience matches some of the most disturbing findings of the US Senate report, the product of a five-year review by Democratic staffers of 6.3m internal CIA documents. CIA officials and many Republicans dismissed the report’s findings as exaggerated.

Years before the report was released, Khan complained to his lawyers that he had been subjected to forced rectal feedings. Senate investigators found internal CIA documents confirming that Khan had received involuntary rectal feeding and rectal hydration. In an incident widely reported in news media after the release of the Senate investigation, CIA cables showed that “Khan’s ‘lunch tray’, consisting of hummus, pasta with sauce, nuts, and raisins, was ‘pureed’ and rectally infused”.

The CIA maintains that rectal feedings were necessary after Khan went on a hunger strike and pulled out a feeding tube that had been inserted through his nose. Senate investigators said Khan was cooperative and did not remove the feeding tube.

Most medical experts say rectal feeding is of no therapeutic value. His lawyers call it rape.

Khan told his lawyers that some of the worst torture occurred in a May 2003 interrogation session, when guards stripped him naked, hung him from a wooden beam for three days and provided him with water but no food. The only time he was removed from the beam was on the afternoon of the first day, when interrogators shackled him, placed a hood over his head and lowered him into a tub of ice water.

Majid Khan is pictured in this 2009 handout photograph taken at Guantánamo Bay. Photograph: Handout/Reuters

An interrogator then forced Khan’s head underwater until he feared he would drown. The questioner pulled Khan’s head out of the water, demanded answers to questions and again dunked his head underwater, the detainee said. Guards also poured water and ice from a bucket on to Khan’s mouth and nose.

Khan was again hung on the pole hooded and naked. Every two to three hours, interrogators hurled ice water on his body and set up a fan to blow air on him, depriving him of sleep, he said. Once, after hanging on the pole for two days, Khan began hallucinating, thinking he was seeing a cow and a giant lizard.

“I lived in anxiety every moment of every single day about the fear and anticipation of the unknown,” Khan said, describing his panic attacks and nightmares at the black site. “Sometimes, I was struggling and drowning under water, or driving a car and I could not stop.“

In a July 2003 session, Khan said, CIA guards hooded and hung him from a metal pole for several days and repeatedly poured ice water on his mouth, nose and genitals. At one point, he said, they forced him to sit naked on a wooden box during a 15-minute videotaped interrogation. After that, Khan said, he was shackled to a wall, which prevented him from sleeping.

When a doctor arrived to check his condition, Khan begged for help, he said. Instead, Khan said, the doctor instructed the guards to again hang him from the metal bar. After hanging from the pole for 24 hours, Khan was forced to write a “confession” while being videotaped naked.

Khan’s account also includes previously undisclosed forms of alleged CIA abuse, according to experts. Khan said his feet and lower legs were placed in tall boot-like metal cuffs that dug into his flesh and immobilized his legs. He said he felt that his legs would break if he fell forward while restrained by the cuffs.

Khan is not one of the three people whom current and former CIA officials say interrogators were authorized to “waterboard”, a process whereby water is poured over a cloth covering a detainee’s face to create the sensation of drowning. Nor is he the fourth detainee whose waterboarding was documented by Human Rights Watch in 2012.

His descriptions, however, match those of other detainees who have alleged that they were subjected to unauthorized interrogation techniques using water. Human-rights groups say the use of ice water in dousing and forced submersions is torture.

Khan’s account also includes details that match those of lower-level detainees who have described their own interrogations. Like other prisoners, Khan said he was held in complete darkness and isolated from other prisoners for long periods. To deprive him of sleep, his captors kept the lights on in his cell and blared loud music from Kiss and other American rock and rap groups.

He said that he was given unclean food and water that gave him diarrhea and that he was held in an outdoor cell and in cells with biting insects. Other prisoners later told him they were held in coffin-shaped boxes.

Conditions improved significantly in 2005, after the US Congress passed the Detainee Treatment Act. That measure includes anti-torture provisions sponsored by Senator John McCain, who was tortured as a prisoner in Vietnam.

Khan is scheduled to be sentenced by a military judge in Guantánamo Bay by February. His lawyers, however, want his case moved to the US federal courts because, they said, federal law allows for fairer sentences for cooperating witnesses.

“He has made a decision to trust the US government and cooperate with the US government in order to try to atone for what he did,” said J Wells Dixon of the Center for Constitutional Rights. “But it is incumbent on the United States to treat him fairly.”

Katya Jestin, a former federal prosecutor who also represents Khan, said Khan remains committed to cooperating in the military commission system. But, she said, “from a broader criminal justice policy perspective, I would like to see him sentenced in US federal court. Federal judges have more experience in assessing the value of cooperation and incentivizing cooperation from others.”