BOISE, Idaho (AP) — The Defense Department will investigate the crash of an Idaho Army National Guard helicopter during a training mission that killed both people aboard, a military spokesman says.

National Guard spokesman Col. Tim Marsano confirmed the deaths of the two male pilots but did not release any details on them pending notification of relatives.

The Apache combat helicopter crashed around 7 p.m. Thursday about two miles south of the National Guard base at Gowen Field near Boise International Airport, Marsano said. It wasn’t immediately clear whether the pilots were heading to or returning from a mission, he said.

Marsano said he 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.

The Idaho Guard has a training area about 20 miles south of Gowen Field, but pilots also train over other areas, the spokesman said.

“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. “Our thoughts and prayers are with their families.”

Boise firefighters initially responded to the crash but then turned the scene over to the National Guard, Fire Chief Dennis Doan said.

Ada County sheriff’s deputies secured the site and blocked media access.

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