An Iowa man went home and grabbed a loaded gun after having an argument with another man at a bar early Thursday morning, then returned to the bar and shot the other man in the face, killing him.

Colby Nelson, 19, was pronounced dead in the parking lot of Bootleggers Bar and Grill in Clearfield, according to a probably cause affidavit filed in district court of Taylor County.

Alan James Schultz, 37, waited at the scene for police to arrive and admitted killing Nelson. He has been charged with first degree murder.

Taylor County Sheriff’s deputies responded to the scene just after 3:30 a.m. and found Nelson with a gunshot wound to the head. Schultz was leaning against an SUV near the body and readily acknowledged he had shot the teen. He admitted he was the killer again after he was brought to the sheriff’s office and was interviewed by a state Department of Criminal Investigation agent.

Investigators said the two men had argued while inside the bar earlier in the night and again outside the establishment as Schultz was leaving. That’s when Schultz went home on his motorcycle, grabbed a loaded handgun, and drove back to the bar in a different vehicle.

He got out of the vehicle and confronted Nelson and “several other individuals” in the street outside the bar, then walked back to his car and grabbed the loaded handgun. He recrossed the street and again confronted Nelson, then shot him in the face. Schultz unloaded the weapon and put it on the ground, then waited by his car for police to arrive.

The Department of Criminal Investigation said the probe is ongoing.

Investigators didn’t say what the argument was about.