"I won't say he's gone 180, but he's realized that the best way of getting information is not to beat or abuse detainees," Colonel Davis said as he stood in the operations room, the walls plastered with maps of Baghdad.

They both severely and repeatedly kicked and beat detainees with fists, truncheons, sticks and rifle butts.

An investigation by immigration officials concluded that Esmor, trying to cut costs, had failed to train guards, some of whom beat detainees.

In this case, American troops found evidence of "unchecked torture," including a wooden pallet and a rubber hose, implements that were often used to beat detainees on their backs and the soles of their feet.

There was regular cruel treatment and infliction of great suffering, with HVO soldiers and guards routinely beating detainees, often to the point of unconsciousness and severe injuries.

According to The Guardian, during Nelson's trial a tape of a confession Nelson made in 2007 was played, that offered: "a grisly account that Nazario beat detainees, killed two of them by shooting them in the forehead and ordered squad members to kill the other two."

It added that Russian officials had acknowledged that law enforcement officials had tortured and severely beat detainees and inmates.

Investigators said they had found ample evidence that underpaid and poorly trained guards had beaten detainees, singling out the midnight shift as particularly abusive.

Guards at detention centers systematically beat Chechen detainees, some of whom have also been raped or subjected to other forms of torture.