DENVER (AP) — A Colorado State Patrol trooper is John Caldwellrecovering after he was shot in the arm during a shootout near Denver that left the gunman dead, authorities said.

Cpl. Tye Simcox was in his parked pickup in the center median of U.S. 36 on Saturday afternoon when a passing driver fired at him multiple times with a semi-automatic pistol, The Denver Post reported. The gunman, whose name has not been released, then pulled over, got out of his vehicle and fired more shots through the windshield of the marked patrol vehicle.

Simcox got out of the truck with his rifle and returned fire, killing the suspect, said Col. Matthew Packard, chief of the Colorado State Patrol.

“I will tell you very directly that our member was targeted today by a man that intended to kill him, and that is shocking and unacceptable,” Packard said during a news conference Saturday evening.

Simcox applied a tourniquet to his arm as he waited for state patrol troopers and Westminster police officers to arrive. He was treated and released from a hospital.

Investigators do not know why the gunman attacked the trooper, Packard said.

“I want it to be known that we came out on top today, and that’s really, really important, because that’s what good does,” Packard told reporters. “Good and courageous people win over evil cowardice — and that’s what happened today on Highway 36.”