“There are dozens of people I know it happened to because it happened to me,” he said. Abu Ali was snatched during a raid in his Shia neighbourhood in mid-September and held for six weeks in a similar secret facility, where he and 20 other detainees were subjected to repeated torture.

Such violence, he insisted, was nothing unusual in the prison at a complex in central Baghdad known as the “security school” during the Saddam Hussein era.

“We were all tortured very badly,” he said. “I was handcuffed with my hands behind my back and then hanged from a hook in the ceiling. Then they tied a rope to my legs and pulled until I lost consciousness or my limbs were dislocated. Sometimes they electrocuted us by putting wires on our testicles. And then, of course, every day they would beat us.”

As Abu Ali recounted his story yesterday, Bayn Jabr, the Interior Minister and the senior official at the centre of the scandal, angrily denied on Iraqi television the allegations of systematic torture. He said that only five or six of 173 detainees had been badly harmed and they were among the country’s most dangerous terrorists.

Other officials have been more forthcoming about the extent of the abuse. Ali Kalib Khadher, the Deputy Minister for Police Affairs, blamed the “heritage of violence” left over from Saddam’s three decades in power. He added, however: “There has been much exaggeration about this issue. No one was beheaded, no one was killed.”

Sunni groups, who have long alleged that detentions, torture, assassinations and mass killings are part of a “dirty war” being waged against them by the Shia-dominated security forces, insist that there are many such detention facilities where similar activities are taking place.

They have released photographs showing injuries from torture but have refused to pinpoint the facilities, fearing that the security forces will kill detainees to remove evidence of wrongdoing. The US military has vowed to uncover any additional facilities and has supported the Iraqi Government’s promise of an investigation. But the Sunni groups, who have demanded international involvement, remain sceptical, alleging that the Americans have long been aware of such abuses without taking action.

Abu Jamal, a Sunni bookseller, is certain that the Americans know about the torture inflicted on his son after he was arrested by Interior Ministry commandos. When he eventually tracked down Jamal Hamdani, he was being treated in a US military hospital in Camp Bucca, Umm Qasr.

The 30-year-old was left impotent and paralysed on one side of his body after repeated electrocution of his spine and genitals during two months in detention in a secret prison in Kadhamiya, Baghdad. In addition, an electric drill had been used on his chin.

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