Exodus 12:28-29

12:28 and the Israelites went away and did exactly as the Lord had commanded Moses and Aaron.

The Deliverance from Egypt

12:29 It happened at midnight – the Lord attacked all the firstborn in the land of Egypt, from the firstborn of Pharaoh who sat on his throne to the firstborn of the captive who was in the prison, and all the firstborn of the cattle.