SAN JUAN, Puerto Rico – Videotapes of riot squads subduing troublesome terror suspects at the American prison camp at Guantanamo Bay show the guards punching some detainees, tying one to a gurney for questioning, and forcing a dozen to strip from the waist down, according to a secret report. One squad was all-female, traumatizing some Muslim prisoners.

Investigators from U.S. Southern Command at Miami, which oversees the camp in Cuba, wrote the report that was obtained by the Associated Press after spending a little over a week in June reviewing 20 hours of videotapes involving “Immediate Reaction Forces.”

The camp’s layout prevented videotaping in all the cells where the five-person teams – also known as “Immediate Response Forces” – operated, the report said. Reviewers said they did not look at all of the available videotapes.

Although the report cited several cases of physical force, reviewers said they found no evidence of systemic detainee abuse, according to the six-page summary dated June 19, 2004. An official familiar with the report authenticated it, speaking to AP on condition of anonymity. AP also reviewed an unclassified log of the videotape footage.

The tapes raised questions about mistreatment and misconduct, however, said the investigators, who suggested some clips needed more scrutiny to rule out abuse. The military has cited 10 substantiated cases of abuse at Guantanamo, and announced yesterday an extension would be granted for investigators to interview witnesses in America and abroad.

A memo describing one video clip says: “A detainee appears to be genuinely traumatized by a female escort securing the detainee’s leg irons.”

The American military wouldn’t comment on whether there’s a specific strategy involved in using an all-female response force but said female guards – who serve on mixed reaction teams as well – comprise about 20% of the guard force.