It is a US-run prison built from scratch on an US military base to hold "enemy combatants" captured in the so-called "war on terror".

Those imprisoned there have never been charged with a crime, nor do they have any meaningful way of challenging their detention. The inmates allege abuse at the hands of their captors, ranging from sleep deprivation to brutal beatings. And no, it is not Guantanamo Bay. The Bagram Theatre Internment Facility lies on a sprawling US military complex, 40km northeast of the Afghan capital Kabul. It holds almost three times as many prisoners as Guantanamo and, as its better-known Cuban counterpart prepares to close, the Bagram prison is about to double in size.

You could be forgiven for never having heard of the prison at Bagram. After all, Barack Obama, the US president, does not like to mention it, preferring to concentrate on his flagship policy of closing the Guantanamo Bay prison facility.

Journalists are not allowed to visit and lawyers are banned from the premises. Even the number of prisoners held there remains an official secret. Estimates suggest it currently houses more than 600 but exact details remain classified by US authorities.

While Guantanamo has been in the spotlight in recent years, Bagram has operated in the shadows. The first announcement of detentions at Bagram came in January 2002 and, as the US renditions programme swung into action, the site became a key regional hub in a global network of prisons.

'Terrifying experience'

It was often used as a holding site for those on their way to Guantanamo Bay. Omar Deghayes was held in Bagram in 2002 before he was transferred to Cuba. He says it was a terrifying experience.

"Lying on the floor of the compound, all night I would hear the screams of others in the rooms above us as they were tortured and interrogated," he says.

"My number would be called out, and I would have to go to the gate. They chained me and put a bag over my head, dragging me off for my own turn. They would force me to my knees for questioning, and threaten me with more torture."

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