The report also concluded the CIA quickly overstepped the already broad guidelines for detention and interrogation set down by the Bush administration, and that its own senior ranks soon lost count of the number of detainees its operatives had captured and detained in secret sites around the world. In the dark: US President George W. Bush and Secretary of State Colin Powell were not fully briefed on the CIA's torture techniques and their lack of effectiveness, according to a Senate report. Credit:Getty Images The 499-page executive summary of a 6300-page report that took more than five years to create was released on Tuesday morning in Washington, DC, after months of haggling between the committee, the White House, the CIA and the State Department over redactions. The released document is 7 per cent redacted, with the code names of CIA operatives blanked out, as well as the names of the countries that hosted the facilities. The release has provoked a partisan divide in the capital, with many Republicans declaring that it has endangered American interests around the world. But the committee's chairwoman, Democratic Senator Dianne Feinstein – who has a long record of support for the CIA – insisted on the report's release.

The CIA was this year forced to apologise to the committee for illegally spying on its staff as they conducted their investigation. A bouquet left by the Duke and Duchess of Cambridge at the September 11 Memorial's Reflection Pool in New York this week. The CIA's torture program had its genesis in the response to the terrorist attacks of September 11, 2001. Credit:Getty Images The former vice-president, Dick Cheney, an architect of the war on terrorism and supporter of harsh interrogation has called the report's conclusions "a crock". He told The New York Times the program had been "the right thing to do, and if I had to do it over again, I would do it". Exposing CIA actions: Senate intelligence committee chairwoman Dianne Feinstein announces in Washington the findings of the report into CIA torture techniques and their effectiveness. Credit:AP

He said the CIA deserves a lot of praise for what it achieved. "What I keep hearing out there is they portray this as a rogue operation and the agency was way out of bounds and then they lied about it. I think that's all a bunch of hooey. Mistreated: Terror suspect Abu Zubaydah was subjected to simulated drowning, or waterboarding, and sleep deprivation. Credit:AP "The program was authorised. The agency did not want to proceed without authorisation, and it was also reviewed legally by the Justice Department before they undertook the program." As expected, the report reveals in chilling detail the brutality of some of the CIA's techniques.

Specific examples of brutality by CIA interrogators cited in the report include the November 2002 death from hypothermia of a detainee who had been held partially nude and chained to a concrete floor at a secret CIA prison. Some were deprived of sleep for up to 180 hours, at times with their hands shackled above their heads, and subjected to "rectal feeding" or "rectal hydration" without any documented medical need. The report describes one secret CIA prison, whose location is not identified, as a "dungeon" where detainees were kept in total darkness, constantly shackled in isolated cells, bombarded with loud noise or music, and given only a bucket in which to relieve themselves. The report documents details how the interrogation of the captive Abu Zubaydah appears to have traumatised two civilian CIA contractors charged with training CIA operatives in the techniques. In the report the contractors are referred to by the pseudonyms Grayson Swigert and Hammond Dunbar (The New York Times has named these men as psychologists James E. Mitchell and Bruce Jessen). According to the report Abu Zubaydah, who had already agreed to co-operation, was subjected to enhanced interrogation nearly 24 hours a day for 19 days after being held in complete isolation for 47 days.

During his interrogation a collar made from a towel was used to slam his head into walls, he was kept in stress positions and or in a coffin-shaped box and waterboarded regularly as medical staff stood by to keep him alive. Waterboarding involves pouring water over a cloth covering a restrained victim's face, causing the individual to experience the sensation of drowning. A medical officer wrote to superiors in an email entitled "And so it begins": "The sessions accelerated rapidly progressing quickly to the waterboard after large box, walling, and small box periods. [Abu Zubaydah] seems very resistant to the waterboard. Longest time with the cloth over his face so far has been 17 seconds. This is sure to increase shortly. NO useful information so far ... He did vomit a couple of times during the waterboard with some beans and rice. It's been 10 hours since he ate so this is surprising and disturbing. We plan to only feed Ensure [a nutritional supplement] for a while now. I'm head[ing] back for another waterboard session." The report found documents recording how some CIA operatives present responded to the interrogation, noting that it was "visually and psychologically very uncomfortable". A day later a note was made saying: "Today's first session had a profound effect on all staff members present ... it seems the collective opinion that we should not go much further ... everyone seems strong for now but if the group has to continue ... we cannot guarantee how much longer," and later that day, "Several on the team profoundly affected ... some to the point of tears and choking up." The report found that plans were in place to cremate and dispose of him if he died in interrogation.

In a statement the CIA acknowledged "shortcomings" in the detention and interrogation program and that "the agency made mistakes". But the statement said its own review found the program "did produce intelligence that helped thwart attack plans, capture terrorists, and save lives". US President Barack Obama, who banned "enhanced interrogation" on his election, said in a statement the methods "were not only inconsistent with our values as nation, they did not serve our broader counterterrorism efforts or our national security interests". "Moreover, these techniques did significant damage to America's standing in the world and made it harder to pursue our interests with allies and partners." The only leading Republican to support the release of the report was Senator John McCain, who was tortured during the Vietnam War.

"Most of all, I know the use of torture compromises that which most distinguishes us from our enemies," he said. "Our belief that all people, even captured enemies, possess basic human rights which are protected by international conventions, [which] the United States not only joined but for the most part, authored. "I dispute wholeheartedly it was right for [CIA officers] to use these methods, which this report makes clear were neither in the best interest of justice, nor our security, nor the ideals we have sacrificed so much blood and treasure to defend," he said. with Reuters