What began as a routine response to a brush fire on northern Idaho’s Canfield Mountain turned deadly Sunday after firefighters reported someone shooting at them while they battled the flames.

Wess Roley, 20, was found dead with a gun nearly six hours after the attack, and investigators say he acted alone, according to the Associated Press.

Wess Roley is suspected of killing two firefighters and wounding a third in Idaho, Kootenai County Sheriff Robert Norris said Monday.