"The two OH-58D helicopters were engaged and struck by hostile fire while conducting a reconnaissance mission," Fort Drum spokeswoman Julie Cupernall said Friday.
The investigation continues, Cupernall said. A Sunni nationalist group had claimed responsibility for the helicopter attack in a posting on an extremist Web site.
The Army report was released after a memorial service for the soldiers at Fort Drum, where they were based.
The pilots were identified as Philip Windorski Jr., 35, of Bovey, Minn.; Matthew Kelley, 30, of Cameron, Mo.; Joshua Tillery, 31, of Beaverton, Ore.; and Benjamin Todd, 29, of Colville, Wash. They were warrant officers in the 10th Mountain Division's 10th Combat Aviation Brigade.
A ceremony honoring the pilots was held Thursday evening at Fort Drum, with family members and fellow soldiers sharing memories of the men. All four pilots were married and had children.
