HENDERSON, Ky. — Police say the man who opened fire at a western Kentucky plastics plant warned his girlfriend two hours before his rampage that he would kill his boss.

Twenty-five-year-old Wesley Higdon of Henderson fatally shot five co-workers before turning the gun on himself early Wednesday.

Authorities say Higdon had an argument with his supervisor about wearing safety goggles Tuesday night, then called his girlfriend and said he was going to kill him.

Officials say he killed the supervisor outside the building, then went back inside and kept shooting in a break room and on the plant floor. Then, he killed himself.

Another person was wounded, and is hospitalized.