Numbers 35:16-19

16Murderers are different. You must kill a murderer. Maybe someone hits another person with a heavy iron tool. If the person dies, the murderer must also die.

17Someone might hit another person with a big stone. If the person dies, the man is a murderer. He must die.

18A man might hit a person with a dangerous weapon made from wood. If the person dies, the man is a murderer. He must die.

19The dead person's relative himself must kill the murderer when he meets him.