BOISE, Idaho (AP) — Two chief warrant officers were killed when their Apache attack helicopter crashed during a training mission near the Boise airport, the Idaho Army National Guard said Friday.

Stien P. Gearhart, 50, and Jon L. Hartway, 43, were the only two soldiers aboard the aircraft when it went down Thursday evening.

Both were assigned to the 1-183rd Attack Reconnaissance Battalion headquartered at Gowen Field in Boise. Gearhart lived in Meridian, Idaho, and Hartway lived in Kuna, Idaho.

The cause of the crash will be investigated by the Department of Defense.

The helicopter crashed about two miles south of the National Guard base near Boise International Airport, Guard spokesman Col. Tim Marsano said. It wasn’t immediately clear whether the pilots were heading to or returning from a mission.

Marsano also didn’t know whether any communication was heard from the helicopter prior to the crash. There was no fire, he said.

The Idaho Army National Guard had 16 Apache helicopters at its Gowen Field training base and a training area about 20 miles south of the field. Pilots also train over other areas.

“The men and women of the Idaho National Guard are united in grief at the loss of two of our brothers in arms, who gave their lives while training to defend our nation,” Maj. Gen. Gary Sayler, commander of the Idaho National Guard, said in a statement.

Idaho Gov. C.L. “Butch” Otter echoed those feelings.

“This tragedy reminds us of the enormous sacrifice and great risk involved in military service – whether here at home preparing to go into harm’s way or on the battle lines of freedom,” Otter said in a prepared statement.

All four members of Idaho’s congressional delegation issued statements saying they were praying for the families of the men.

Marsano said the families had requested privacy.

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