"Their detention outside the U.S. enables CIA interrogators to apply interrogation methods that are banned by US law, and to do so in a country where cooperation with the Americans is particularly close, thereby reducing the danger of leaks," the article said, citing unnamed intelligence sources.

Khalid Sheikh Mohammed is one of the masterminds behind the 9/11 attacks in the US,  while Hambali, or Riduan Isamuddin, is said to be al Qaeda's ally in southeast Asia. Abu Zubaydah was a member of Osama bin laden's inner circle.

The curious case of Khalid Sheikh

The article, written by Yossi Melman, did not specify an exact location for the 'ghost prison,'  but said at least 11 senior al-Qa'eda and other militant leaders were being held in Jordan.

Haaretz also quoted a Human Rights Watch report as saying that the CIA was granted special permission by the US law enforcement authorities to operate "other laws" at the secret facility with regard to interrogation methods.

'Detainees are subjected to physical and psychological pressure that includes the use of simulated drowning, loud music, sleep deprivation, and sensory deprivation. Some of these methods were exposed with the revelation of torture techniques used by American interrogators at the Abu Ghraib prison in Iraq,' it said.

'The HRW report charges that the US thereby is in breach of all international conventions, including the Geneva Convention on prisoners of war, by refusing prisoners access to the Red Cross or their families,' Haaretz said.

Mordechai Kedar, of Bar Ilan University, a Middle East expert and former Israeli military intelligence officer, said the story was highly credible.

"Yossi Melman is well woven into intelligence circles and has good access to intelligence information and he bases his reports on hard-core information," he said. "This sounds reasonable, logical, and there is an historical basis too because of the long-standing hatred between the Hashemite kingdom and Wahhabis [hardline Muslims], who are seen as running al-Qa'eda," he said.

The CIA has declined comment. But a Jordanian official, who declined to be named, said: "The allegations that surface every now and then that the US runs secret detention centres in the kingdom are totally baseless and seek to undermine the country's favourable human rights image abroad."

America's war on terror