Samir Naji of Yemen was cleared for release in 2009, but still remains in detention.

CNN reports he gave a graphic account of how he was treated inside Guantánamo in a recent meeting with lawyers from Reprieve, an international human rights organisation.

In the account, Naji claimed he was kept in “a tiny, freezing cold cell, alone”, living in fear of what interrogators would do to him as the days, weeks and years went by.

“That’s when you hold yourself in a ball, and fight to ignore the confusion of what has just happened to you, and the fear of what might be coming next. Or the fear that comes when you realise that no one is coming to help; that the life, family and friends you knew are all far, far away,” he said.

During his first three long months of CIA interrogation, Naji said each session began with shouting as a wake up call before he was struck on his face and back. He was later injected with an unknown substance.

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Brutally tortured ... Samir Naji, who gave a first person account of life inside Guantánamo Bay. Source: Supplied

“I am so desperate for sleep, my head is swimming. There are photographs of faces stuck all around the walls of this room. They demand that I identify the individuals, but I can barely focus to see if I might know them. The shouting and the insults get louder, and then they nod to a man in the corner. He injects me twice in the arm with some unknown substance. It’s the last thing I know,” he said.

When Naji refused to eat food, one interrogator poured an army pack on his head, CNN reports.

“They tell the man in the corner to start feeding me intravenously. He inserts the tube in two different places on my arm and makes it bleed,” he said.

Unable to hold out from eating, Naji recalled how they threw food on the floor for him to eat.

They then threaten him with rape if he wet himself.

Behind wire ... guards escorting a Guantanamo detainee carrying a book at the USA Military Base in Guantánamo Bay, Cuba. Source: AP

“I tell the interrogators that I can’t face not eating any more. They throw food on the floor of the room and tell me to eat like a pig. They won’t let me go to the restroom. They watch as it gets more painful, and laugh as they get the translator to describe how they will rape me if I pee in my pants.”

In one interrogation room, Naji said he was forced to watch footage of other prisoners being tortured, before they touch his private parts if he does not dance for them.

“I’m in a sort of cinema room, where I have to watch videos of other prisoners being abused. Then they tell me that I have to dance for them, and run in circles whilst they pull on my chains. Every time I try and refuse, they touch me in my most private areas,” he recalled.

Naji also spoke of being taken to a pornography room, where he is stripped naked, and forced to make animal sounds while being shown naked images of women.

Under scrutiny ... a detainee from Afghanistan is carried on a stretcher before being interrogated by military officials at Camp X-Ray at the USA Naval Base in Guantánamo Bay in 2002. Source: News Limited

“Now it’s the pornography room. Awful pictures everywhere. There is one with a man and a donkey. I’m stripped naked and have my beard shaved, in a gratuitous insult to my religion. I’m shown pornographic pictures of women. I’m told to make the noises of different animals, and when I refuse, they just hit me. It ends with them pouring cold water all over me.”

Later, he is eventually taken to a doctor for medical treatment after being found beaten and “nearly frozen” in his prison cell.

Naji’s horrific account of what happened inside Guantánamo Bay comes after the controversial report into the CIA’s extreme methods of torture was released this week.

CIA Director John Brennan has now struck back at the US Senate report saying “abhorrent” tactics were used but the program saved lives after the September 11, 2001 attacks.

Brennan conceded that it was “unknown and unknowable” whether the harsh treatment during George W. Bush’s presidency yielded crucial intelligence that could have been gained in any other way. But he said there is no doubt that detainees subjected to the treatment offered “useful and valuable” information afterwards.

Forced to wait ... detainees wearing orange jump suits sit in a holding area at the temporary detention facility Camp X-Ray on Guantánamo Bay. Picture: AP Source: News Limited

The report said that none of the agency’s “enhanced interrogations” provided crucial information. It cited the CIA’s own records, documenting in detail how waterboarding and lesser-known techniques such as “rectal feeding” were actually employed.

The CIA chief also appeared to draw a distinction between interrogation methods, such as water boarding, that were approved by the Justice Department at the time, and those that were not, including “rectal feeding,” death threats and beatings. He did not discuss the techniques by name.

“I certainly agree that there were times when CIA officers exceeded the policy guidance that was given and the authorised techniques that were approved and determined to be lawful,” he said. “They went outside of the bounds. ... I will leave to others to how they might want to label those activities. But for me, it was something that is certainly regrettable.”

But Brennan defended the overall detention of 119 detainees as having produced valuable intelligence that, among other things, helped the CIA find and kill al-Qaeda leader Osama bin Laden.

Dead man ... al Qaeda leader Osama bin Laden before he was killed in Pakistan. Picture: AP Source: AP

The 500-page Senate report exhaustively cites CIA records to dispute that contention. The report points out that the CIA justified the torture — what the report called an extraordinary departure from American practices and values — as necessary to produce unique and otherwise unobtainable intelligence.

Seeking to put the controversy in context, Brennan stressed that the CIA after the attacks was in “uncharted territory,” having been handed vast new authorities by a president determined to thwart the next al-Qaeda attack.

“We were not prepared,” said Brennan, who was deputy CIA executive officer at the time. “We had little experience housing detainees, and precious few of our officers were trained interrogators.”

Shackled detainee ... clutching paperwork is escorted by two gloved military personnel to an Annual Review Board Hearing in Camp Delta at Guantánamo Bay. Picture: AP Source: News Limited

In starker terms than CIA officials have used previously, Brennan, a career CIA analyst, acknowledged mistakes when the agency took captured al-Qaeda operatives to secret prisons and began using brutal methods in an effort to break them.

“In a limited number of cases, agency officers used interrogation techniques that had not been authorised, were abhorrent and rightly should be repudiated by all,” he said.

But he also said, “The overwhelming majority of officers involved in the program at CIA carried out their responsibilities faithfully. ... They did what they were asked to do in the service of our nation.”

Brennan denied that the CIA intentionally misled lawmakers.