Shemot 8:18-19

And the chartumim did so with their secret lore to bring forth kinim, but they could not: so there were kinim upon adam, and upon behemah. Then the chartumim said unto Pharaoh, This is the Etzba Elohim (Finger of G-d): and the lev Pharaoh was hardened, and he paid heed not unto them; as HASHEM had said.