BAGHDAD, Iraq — U.S. military officials announced Thursday the discovery of three more secret prisons, like two others where Sunnis claimed they were tortured.

The Iraqi police who run them, U.S. officials say, have been infiltrated by Shiite militias that target Sunnis, and can no longer be trusted.

NBC News spoke to an Iraqi policeman, Ahmed, a 22-year-old Shiite, who did not want to show his face, but agreed to speak candidly and coldly about how things are done in Baghdad.

Ahmed (translated): As soon as a person is brought in, he is severely beaten until there is a confession. Some confess without even committing a crime.

That can be just the beginning.

Ahmed (translated): The police I consider honorable kill the terrorists they capture. If we brought them back to the station, they might to bribe their way out.

That’s how journalist Kamal Samaraie, a Sunni, says he got out. He had been picked up after criticizing police conduct in a newspaper.

Kamal Samaraie: I was blindfolded and someone kicked me in my face and broke my teeth.

He says police hung him upside down and clubbed him with a metal pipe.

Kamal Samaraie: They whispered to me, there’s no freedom, you can’t write what you want.

The U.S. always wanted an aggressive police force in Iraq, and helped the interior ministry create a paramilitary wing last year to fight insurgents.

But officials say that changed when the Shiite interior minister who took over last April rapidly expanded the program, enlisting the militias.

At a police commando base, officers were adamant they respect human rights, but added they’re on the frontline of a war that can be messy.

U.S. military commanders says reports of widespread torture are credible. Today, they announced plans to embed hundreds more U.S. troops with Iraqi police to reign in a force they helped create, but which now seems out of control.

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