The United States has botched the handling of inmates at Guantanamo, holding men for years without reliable evidence while releasing others who posed a grave threat, according to leaked secret documents.
The trove of classified files released by the anti-secrecy website WikiLeaks showed US officials struggling with often flawed evidence and confused about the guilt or innocence of detainees held at the prison at the US naval base in Guantanamo Bay, Cuba, media reported Monday.
Hundreds of inmates who turned out to have no serious terror links were held without trial, based on vague or inaccurate information, including accounts from unreliable fellow detainees or statements from men who had been abused or tortured, the New York Times quoted the documents as saying.
One poor Afghan farmer with no ties to militants was held for two years without trial in a case of mistaken identity, the documents showed.
But US authorities in 2004 decided to release Abdullah Mehsud, a Taliban extremist who duped his interrogators into believing he had been conscripted by the insurgents as a driver.
"Detainee does not pose a future threat to the US or US interests," said a 2003 document, quoted by the Times.
Mehsud, who gave a false name to his American interrogators, was sent back to Afghanistan where he organized a Taliban unit to assault US troops, planned an attack on Pakistan's interior ministry that claimed 31 lives, oversaw the kidnapping of two Chinese engineers and set off a suicide bomb in 2007 in Pakistan -- winning praise from Al-Qaeda chief Osama bin Laden.
President Barack Obama's administration, which has struggled to close the controversial Guantanamo prison, denounced the "unfortunate" release of the classified documents, part of a massive cache of secret memos leaked to WikiLeaks last year.
The government said in a statement the Obama and Bush administrations had "made every effort to act with the utmost care and diligence in transferring detainees from Guantanamo."
The New York Times was among a group of US and European media outlets that obtained the 779 secret documents, including The Washington Post, National Public Radio, The Daily Telegraph, El Pais, Le Monde, Der Spiegel and La Repubblica.
In another revelation, one document reportedly showed that a top detainee, senior Al-Qaeda commander Khalid Sheikh Mohammed, claimed that a nuclear bomb had been hidden somewhere in Europe to be detonated if bin Laden is ever caught or killed.
At least 150 detainees brought to Guantanamo were innocent Afghans or Pakistanis, including drivers, farmers and chefs, according to The Daily Telegraph.
They were rounded up as part of frantic intelligence-gathering in war zones and then detained at the US naval base in southeastern Cuba for years due to incorrect information or simply for being at the wrong place at the wrong time, the British daily said.
Overall, US military analysts considered only 220 of all the suspects detained at Guantanamo to be dangerous extremists.
Another 380 were deemed to be low-ranking foot soldiers who traveled to Afghanistan or were part of the Taliban, the Telegraph wrote.
In dozens of cases, senior US commanders were said to have concluded that there was "no reason recorded for transfer" to Guantanamo Bay.
However, about a third of the 600-some men who have been transferred to third countries from Guantanamo were branded "high-risk" before being released or handed to other governments, The New York Times said.
Of the 172 prisoners who remain at Guantanamo, 130 have been rated as posing a "high-risk" threat.
The Times said the files, which detail the background of each of the 779 people who have passed through the prison facility since 2002, revealed little about harsh interrogation tactics reportedly used at Guantanamo that sparked widespread condemnation around the world.