The names of the soldiers and their unit were not released, and the statement gave few details. A military spokesman said the unit comprised an entire company.

"None of the insurgents required medical treatment for injuries related to the alleged assault," the command statement said. "Only one of the suspected terrorists remains in custody of coalition forces at this time."

According to the U.S. statement, the Army's Criminal Investigation Division has begun an inquiry that will determine whether the military orders the soldiers to stand trial.

"All Task Force Baghdad soldiers are expected to act appropriately and to treat all persons under their control with dignity and respect. Allegations of illegal activities will always be thoroughly investigated," said Lt. Col. Clifford Kent, a Task Force Baghdad spokesman. "The unit involved has been pulled off line to complete the inquiry and retraining."

U.S. commanders have been especially sensitive to alleged mistreatment of detainees since the abuse of inmates at the Abu Ghraib prison triggered a major scandal.