'Moazzam Begg, 37, who was freed by the Metropolitan Police without charge and reunited with his wife and four children after three years' imprisonment, also accuses his American captors of beating two detainees to death at the Bagram air base near Kabul in Afghanistan,' the British daily said.
In his first interview since his release, he told Channel 4 News he "witnessed two people get beaten so badly I believe it caused their deaths".
'Suspects threatened with Guantanamo torture'
Begg admits having visited militant training camps in Afghanistan in 1993 and again in 1998. But the first was run by the Northern Alliance fighting the Taliban, while the other was run by Kurds opposed to Saddam Hussein, and not by the Al Qaeda, he claims.
Begg, who was in Afghanistan when 9/11 occurred, was later arrested in Islamabad by US security officers who raided his flat.
"There was a knock, about 12 o'clock at night. I answered the door ... a gun was put to my head and I was ... made to kneel. A black hood was put on my head, my hands were tied behind my back and my legs were shackled and I was carried into a vehicle ... and driven off. Never got a chance to say goodbye or a word to my wife or my children," he said.
More US probes into prisoners abuse
The former law student and bookshop owner from Birmingham was then taken to Bagram in Afghanistan, and then to Guantanamo Bay in Cuba in February 2003 with hundreds of other 'unlawful combatants.'
'Shackled and dressed in orange jumpsuits, they were held without charge, trial or access to lawyers. For much of his detention he was in solitary confinement, often exposed to extreme weather and deprived of basic necessities,' The Independent said.
While his detention at Guantanamo as "tortuous," his specific charges of torture involve his treatment at Bagram. In one such case, he faced two FBI agents who ordered punishments which included being "hog-tied".
Abu Ghraib abuse 'just for fun'
This involves "having your hands tied behind your back and then simultaneously having them tied to your legs and your ankles and shackled from behind; left on a floor with a bag over my head, and kicked and punched and left there for several hours, only to be interrogated again".
He was threatened with being sent to Egypt, "to be tortured, to face electric shocks, to have my fingers broken, to be sexually abused, and the like," The Independent quoted him as saying.
"I don't think I can ever be back to normality and I'm still trying to work out what normality is. But what's kept me going is my faith and the thoughts of my children," said Begg.
America's war on terror: Complete coverage
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