The Senate Intelligence Committee is set to release a declassified 480-page report on Tuesday on the use of torture by the Central Intelligence Agency after 9/11.

The use of torture -- or what is called enhanced interrogation techniques -- were used on al-Qaida detainees and terror suspects held in secret facilities in Europe and Asia under the Bush Administration. The executive summary report is on 6,000 page secret study, which took five years to complete and cost $40 million to investigate.

The committee investigated the CIA detention and interrogation program active from Sept. 11, 2001 to 2006, and found the agency purposely deceived the U.S. Justice Department to attain legal justification for the use of torture techniques.

The probe, however, did not evaluate the role of former President George W. Bush or top administration officials in approving abuses including torture. The White House had led negotiations to declassify the report since April.

U.S. officials who had read the report say it includes disturbing new details about the CIA's use of techniques as sleep deprivation, confinement in small spaces, humiliation and the simulated drowning process known as waterboarding. The summary condenses the narratives of 20 detainees.

The report also says the torture failed to produce life-saving intelligence, a conclusion disputed by current and former intelligence officials, including CIA director John Brennan, according to McClatchy.

President Barack Obama has acknowledged, "We tortured some folks."

The committee voted this year to release a declassified executive summary and after months of negotiations

Concern is mounting, however, about the timing of the report. Former Central Intelligence Agency director Michael Hayden told CBS's Face The Nation on Sunday that the report's conclusions are not true, but releasing it could be used as justification by terrorist organizations to attack U.S. personnel and facilities abroad.

"First of all, the CIA workforce will feel as if it had been tried and convicted in absentia since the Senate Democrats and their staff didn't talk to anyone actively involved in the program. Secondly, this will be used by our enemies to motivate people to attack Americans and American facilities overseas," Hayden said.

Secretary of State John Kerry called Sen. Diane Feinstein, D-Calif, the chair of the Senate Intelligence Committee, on Friday, according to Bloomberg News, and asked for the report to be delayed arguing it could damage foreign relations, and he had been reportedly warned that allies were concerned that violence could erupt in the Middle East if it is released.

Sen. Feinstein, who is due to step down from chair of the committee at the end of this year, told the Los Angeles Times that the harsh interrogations undermined "societal and constitutional values that we are very proud of. Anybody who reads this is going to never let this happen again."