WASHINGTON, June 16 — American Special Operations soldiers employed a set of harsh, unauthorized interrogation techniques against detainees in Iraq during a four-month period in early 2004, long after approval for their use was rescinded, according to a Pentagon inquiry released today.

The investigation is the last of 12 major inquiries to be made public in reviewing allegations of detainee abuse by American personnel in Cuba, Afghanistan and Iraq,, and it is the first to focus on Special Operations forces, who operate with more latitude than other military units. It detailed harsh treatment that continued at isolated operations bases even after the abuses first surfaced at the Abu Ghraib prison.

Special Operations interrogators gave some detainees only bread or crackers and water if they did not cooperate, according to the investigation by Brig. Gen. Richard P. Formica of the Army. . One prisoner was fed only bread and water for 17 days. Other detainees were locked up for as many as seven days in cells so small they could neither stand up nor lie down, while interrogators played loud music that disrupted their sleep.

The inquiry also determined that some detainees were stripped naked, drenched with water and then interrogated in air-conditioned rooms or outside in cold weather. General Formica said it appeared that technique was used in the case of one detainee who later died during questioning by Navy Seals in Mosul in 2004, but he reported that he had no specific allegations related to that death.

But General Formica recommended that none of the soldiers he investigated be disciplined. He faulted "inadequate policy guidance" from superiors and not "personal failure" for the mistreatment, and he said that none of the Iraqi detainees he later interviewed seemed to be any worse for wear because of the mistreatment.

"Seventeen days with only bread and water is too long," the general concluded. But he added that the military command's surgeon general had advised him "it would take longer than 17 days to develop a protein or vitamin deficiency from a diet of bread and water."

General Formica's review focused on conduct by the Fifth and Tenth Special Forces Groups, which are primarily Army units. It did not cover the actions in Iraq of more highly classified special operations units, including Delta Force and the Navy Seals, or other secretive, specialized units including Task Force 6-26, a subject of extensive allegations of misconduct that were reported by The New York Times in March.

Within the scope of his review, General Formica recommended eight largely administrative changes, including more training for Special Operations interrogators, minimum standards for detention conditions, and new policies regulating the use of indigenous forces who worked with Special Operations soldiers. Pentagon officials said today that all eight had been carried out.

The crux of the problem, General Formica concluded, was that the Special Operations interrogators mistakenly used 5 out of 12 interrogation techniques between February 2004 to May 2004 that Lt. Gen. Ricardo S. Sanchez, then the top commander in Iraq, had withdrawn in October 2003 because military lawyers had determined they were overly harsh.

"It is regrettable," General Formica said in an interview at the Pentagon with three reporters today. "But they were erroneously given the wrong policy."

General Sanchez had approved the techniques in September 2003, to include yelling and blaring loud music and the use of military dogs to frighten Iraqi captives. But confusion over use of the techniques became widespread throughout Iraq, even after they were rescinded a month later. Many of the American captors at the Abu Ghraib prison have also said they believed the techniques were authorized without General Sanchez's prior approval.

The report made public by the Pentagon on Friday was a heavily redacted copy of the 75-page classified document General Formica completed 20 months ago. Members of Congress received briefings on its contents more than a year ago. The Pentagon and Central Command had refused repeated requests since then from The New York Times and other news organizations to provide a declassified version of the report.

Defense Secretary Donald H. Rumsfeld had promised such a version of all major inquires would be made public. But the Pentagon finally made public a declassified version under a Freedom of Information Act request by the American Civil Liberties Union.

At the Pentagon today, General Formica and other senior Defense Department officials underscored that the officer's was not intended to be a wide-ranging review of Special Operations detention and interrogation practices.

In his report, General Formica conducted interviews regarding three separate incidents of alleged detainee abuse involving Special Operations Forces, some of which had been referred from another Army inquiry by Maj. Gen. George R. Fay, whose inquiry examined intelligence personnel. General Formica also reviewed the findings of seven other incidents that were previously investigated.

In the first incident he investigated, General Formica said that allegations by several members of an Iraqi family that American interrogators at Abu Ghraib in December 2003 had beaten, sodomized with a water bottle and slapped them were unsubstantiated by any physical or medical evidence. In addition, he said the family members were known to be insurgent sympathizers.

In the second case, General Formica acknowledged that two Iraqi detainees at an unidentified field station were fed only bread and water for 13 and 17 days, respectively. But he allegations that a former Iraqi policeman and an Iraqi-born Lebanese interpreter, both working with the Americans, had beaten and kicked them were unsubstantiated.

General Formica found that in the third case at a Special Operations field station near Tikrit, three detainees were held in cells four feet high , four feet deep, and 20 inches wide, except to go to the bathroom, to be washed or to be interrogated. He concluded that two days in such confinement "would be reasonable; five to seven days would not." Two of the detainees were held for seven days; one for two days, General Formica concluded.

Of the seven other previously investigated cases General Formica reviewed, , allegations in two were unfounded and one did not involve Special Operations Forces, the report concluded. In two other cases, investigations were still pending when General Formica completed his report in November 2004. A Pentagon spokesman, Lt. Col. Mark Ballesteros, said today that those inquiries were completed but he would not comment on their findings.

Commentary: