The Army has identified four soldiers killed in a helicopter training accident in Colorado.

Those killed in Wednesday's crash were 40-year-old Chief Warrant Officer Terrance Geer, 41-year-old Chief Warrant Officer Robert Johnson, 33-year-old Staff Sgt. Paul Jackson and 28-year-old Staff Sgt. Chad Tucker.

The soldiers identified Friday were all members of Delta Company, 1st Battalion, 160th Special Operations Aviation Regiment at Fort Campbell.

Army Special Operations Command officials say their MH-60 Black Hawk helicopter crashed while conducting mountain and environmental training near Colorado's second-highest summit, Mount Massive.

The Army initially said two were killed, one was injured and one was missing. The missing man was found dead late Wednesday, and the injured man died on the way to the hospital Wednesday, said Lt. Col. John Clearwater, a spokesman for the command at Fort Bragg, N.C.

The crew was training in high-altitude mountainous conditions, "much like the environment they operate in Afghanistan," Clearwater said, adding that he didn't know whether the crew had served there.

The helicopter was assigned to the 160th Special Operations Aviation Regiment (Airborne) at Fort Campbell. Soldiers in the 160th are known as "night stalkers" because they specialize in nighttime operations. The regiment's Web site says the 160th has carried out combat operations in Iraq and Afghanistan.

Wednesday's flight began at Peterson Air Force Base in Colorado Springs, which is about 90 miles east of Mount Massive.