Exodus 8:16-19

16And the LORD said to Moses, Say to Aaron, Stretch out thy rod, and smite the dust of the land, that it may become lice throughout all the land of Egypt. 17And they did so; for Aaron stretched out his hand with his rod, and smote the dust of the earth, and it became lice in man, and in beast; all the dust of the land became lice throughout all the land of Egypt. 18And the magicians did so with their enchantments to bring forth lice, but they could not: so there were lice upon man, and upon beast. 19Then the magicians said to Pharaoh, This is the finger of God: and Pharaoh’s heart was hardened, and he hearkened not to them; as the LORD had said.