|US officials were said to have found no reason recorded for some detainees' transfer to Guantanamo [Al Jazeera]
The United States released dozens of so-called "high-risk" detainees from the Guantanamo Bay prison facility and held more than 150 innocent men for years, according to new reports about a trove of leaked military documents.
The more than 700 classified military files, part of a massive cache of secret documents leaked to the whistle-blowing website WikiLeaks, were made available to select US and European media outlets and made public on Sunday.
It was not clear if the media outlets published the documents with the consent of WikiLeaks - and it was not immediately possible to independently verify all of the leaked documents.
The files are reported to reveal new information about some of the men held at the US prison facility in Guantanamo Bay, Cuba, including details of the more than 700 detainee interrogations and evidence the US had collected against the "terror" suspects.
The files - called Detainee Assessment Briefs or DABs - describe the security intelligence value of the detainees and whether they would be a threat to the US and its allies if released.
To date, 604 inmates have been transferred out of Guantanamo while 172 remain detained.
Thousands of pages of the files are reported to reveal that most of the prisoners who remain at Guantanamo - 130 of them - have been rated as posing a "high-risk'" threat to the US if they are freed without rehabilitation or supervision.
Even more of the George W Bush-era "war on terror" suspects were branded "high-risk" before being released or handed to other governments, The New York Times, one of the newspapers that received the documents, reported.
The documents show some inmates were described as more dangerous than previously known to the public and could complicate efforts by the US to transfer detainees out of the prison.
However, the documents also show that dozens of detainees were found to be innocent, after being held for lengthy periods.
At least 150 people were innocent Afghans or Pakistanis, including drivers, farmers and chefs, who were rounded up as part of frantic intelligence gathering, and then detained for years.
In several cases, senior US commanders were said to have concluded that there is "no reason recorded for transfer".
Al Jazeera file
The documents also show instances in which authorities were concerned less with containing dangerous suspects than on extracting intelligence.
Sami al-Hajj was working as an Al Jazeera cameraman when he was arrested in 2001 and sent to Guantanamo
One file shows that Sami al-Hajj, an Al Jazeera journalist held at Guantanamo for six years, was detained partly in order to be interrogated about the news network.
His file states that one of the reasons he was detained was "to provide information on … the Al Jazeera news network's training programme, telecommunications equipment, and newsgathering operations in Chechnya, Kosovo and Afghanistan, including the network's acquisition of a video of UBL [Osama bin Laden] and a subsequent interview with UBL".
Al-Hajj was released in 2008 and has since returned to work for Al Jazeera.
Hundreds of other detainees reportedly underwent aggressive interrogation techniques before it was determined that they were low-level fighters.
The administration of US president Barack Obama criticised the publication of the files as "unfortunate", calling them "sensitive information".
"It is unfortunate that several news organisations have made the decision to publish numerous documents obtained illegally by WikiLeaks concerning the Guantanamo detention facility,'' ambassador Daniel Fried, the Obama administration's special envoy on detainee issues, and Pentagon press secretary Geoff Morrell, said in a joint statement.
But they added that the documents were out of date, and that the administration's Guantanamo review panel, established in January 2009, had made its own assessments.
"The assessments of the Guantanamo Review Task Force have not been compromised to WikiLeaks. Thus, any given DAB (Detainee Assessment Briefs) illegally obtained and released by WikiLeaks may or may not represent the current view of a given detainee."
Obama pledged two years ago to close the prison, but it remains in legal limbo.