A man convicted of killing his father and three members of his stepfamily after becoming enraged by a remark about his late mother was executed by injection after saying: "I'm ready to go."

Douglas Buchanan Jr., 29, said "get the ride started" just before his death Wednesday night.Authorities said Buchanan showed up at the family home with a rifle in September 1987 and an argument erupted over a remark his father made about Buchanan's mother. The elder Buchanan was shot to death.

His son then waited and fatally shot stepbrothers Donnie, 10, and Joel, 13, when they arrived home from school. He killed stepmother Geraldine Buchanan with a gun and knife.