A manhunt is underway in southwest Iowa after a deadly weekend shooting.

Council Bluffs police responded to a home Sunday afternoon and found 21-year-old Devon Theisen on a front porch with a gunshot wound to the head. Theisen was rushed to a hospital where he died. Witnesses told officers 69-year-old Kenneth Still got into an argument with Theisen, grabbed a shotgun and fired one round.

Still reportedly drove off in a green Nissan Xterra with Iowa license plate GOM 262. He’s considered armed and dangerous.