Exodus 12:29-30

At midnight GOD struck every firstborn in the land of Egypt, from the firstborn of Pharaoh, who sits on his throne, right down to the firstborn of the prisoner locked up in jail. Also the firstborn of the animals. Pharaoh got up that night, he and all his servants and everyone else in Egypt—what wild wailing and lament in Egypt! There wasn’t a house in which someone wasn’t dead.