In a statement, WikiLeaks criticised regulations it said had led to abuse and impunity and urged human rights activists to use the documents to research what it called “policies of unaccountability”.
The statement quoted WikiLeaks founder Julian Assange as saying: “The ‘Detainee Policies’ show the anatomy of the beast that is post-9/11 detention, the carving out of a dark space where law and rights do not apply, where persons can be detained without a trace at the convenience of the US Department of Defence.
“It shows the excesses of the early days of war against an unknown ‘enemy’ and how these policies matured and evolved, ultimately deriving into the permanent state of exception that the United States now finds itself in, a decade later.”
A spokeswoman for the US Embassy in London said it had no comment.
In January, UN human rights chief Navi Pillay said the United States was still flouting international law at Guantanamo Bay by arbitrarily and indefinitely detaining individuals.
After the 9/11 attacks, then president George W Bush set up a detention camp at a US naval base at Guantanamo in Cuba after US-led forces invaded Afghanistan. Of the 779 men held there, 167 remained as of mid-September 2012.
WikiLeaks said a number of documents it was releasing related to the interrogation of detainees, and these showed direct physical violence was prohibited.
But it added the documents showed “a formal policy of terrorising detainees during interrogations, combined with a policy of destroying interrogation recordings, has led to abuse and impunity”.
A number of what can only be described as “policies of unaccountability” would also be released, it said. One such document was a 2005 document “Policy on Assigning Detainee Internment Serial Numbers”, it said.
“This document is concerned with discreetly ‘disappearing’ detainees into the custody of other US government agencies while keeping their names out of US military central records — by systematically holding off from assigning a prisoner record number,” the WikiLeaks statement said.
WikiLeaks did not elaborate. But human rights activists say that after the Sept 11 attacks, the CIA used “black sites” in friendly countries to interrogate and sometimes torture suspected militants beyond the reach of normal legal protections.
The programme’s existence has never been officially acknowledged.