The so-called Black Room was part of a temporary detention site at Camp Nama, the secret headquarters of the unit known as Task Force 6-26, the Times said.

The camp, in a former Iraqi military base at Baghdad International Airport, was the first stop for many insurgents on their way to Abu Ghraib prison a few miles away.

The Times said the abuse at Camp Nama began as the Iraqi insurgency intensified in early 2004 and continued after photographs of abuse at Abu Ghraib were made public in April 2004, belying Pentagon assertions that abuse was limited to a small group of reservists at the notorious detention center.

The report was based on interviews with more than a dozen civilian and military Department of Defense personnel who worked with Task Force 6-26. Virtually all of them were granted anonymity to encourage them to speak candidly without fear of retribution from the Pentagon, the Times said.

The critics said the harsh interrogation techniques practiced at Camp Nama yielded little information to help capture insurgents or safe American lives.

Many of their complaints are supported by declassified military documents and e-mail messages from FBI agents who worked with the task force, the Times said.

According to the report, placards posted at the detention area said, "No Blood, No Foul" ¡ª a slogan that meant soldiers could not be prosecuted as long as they did not make detainees bleed.

Prisoners at Camp Nama often disappeared into a detention black hole, barred from access to lawyers or relatives and confined for weeks without charges, the report said.

"The reality is, there were no rules," an unidentified Pentagon official told the Times.

Gen. Bryan D. Brown, the commander of the Special Operations Command, told the Times in a brief exchange on Capitol Hill, "We take all those allegations seriously. Any kind of abuse is not consistent with the values of the Special Operations Command."