Numbers 35:22
Should you accidentally kill someone who was not your enemy. Maybe you shoved him or threw something at him but did not mean to kill him.
Exodus 21:13
If you did not intend to kill someone and I, Jehovah, let it happen anyway, you may run for safety to a place that I have set aside.
Numbers 35:11
select certain cities to be places of refuge. Anyone who unintentionally kills another person may run to them.
Deuteronomy 19:5
For example: when a man goes into the forest with his friend to cut wood, and his hand swings the axe to cut down the tree, and the iron head slips off the handle and strikes his friend so that he dies. He may flee to one of these cities and live.
Joshua 20:3
Anyone who kills someone accidentally and unintentionally may go there for a refuge from the avenger of blood.
Joshua 20:5
If the one looking for revenge follows you there, the people of the city must not hand you over to that one. They must protect you because you killed the person accidentally and not out of anger.