NASHVILLE, TN. (AP) - The Tennessee Army National Guard says 2 of its pilots have been killed in a helicopter crash.

Maj. Gen. Max Haston said in a statement Sunday that 1st Lt. Thomas Joseph Williams Jr. and Chief Warrant Officer 4 Daniel Cole, both of Knoxville, died Saturday when their OH-58D Kiowa Warrior helicopter crashed in Campbell County. He said they were conducting a routine training flight when the crash occurred.

Haston called the crash a "terrible tragedy" and said the cause is under investigation. No other details were immediately available.

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