FALLUJAH, Iraq (AP) — A Black Hawk medivac helicopter, clearly marked with a red cross, crashed Thursday after a witness said it was hit by a rocket, killing all nine U.S. soldiers aboard. In Baghdad, a C-5 transport plane with 63 passengers and crew limped safely back to the airport after being struck by fire from insurgents.

About 80 Iraqi prisoners, meanwhile, were released from Baghdad’s Abu Ghraib prison, but they were not the detainees that U.S. authorities had promised would be freed under a special amnesty.

The military said a U.S. soldier died Wednesday of injuries suffered in a mortar attack that wounded 30 other troops and a civilian west of Baghdad.

The deaths brought to at least 495 the number of Americans killed in Iraq from hostile and non-hostile causes since the start of the war in March, according to the U.S. Central Command and the Department of Defense.

The Black Hawk went down about four miles south of Fallujah, a stronghold of the anti-American insurgency, the 82nd Airborne Division said.

The military said the cause of the crash was not known, but a witness, Mohammed Ahmed al-Jamali, said he heard the distinctive whoosh of a rocket and saw the helicopter, which was clearly marked with red crosses signifying its medical mission, struck in the tail.

The 27-year-old farmer who lives close to the crash site said he rushed to the scene but found everyone dead.