And thus do you find with the Egyptians, that with what they vaunted themselves, He exacted punishment of them, (Exodus 14:7) "And he (Pharaoh) took six hundred chariots and all (the other) chariots of Egypt," and it is written (Ibid. 15:4) "The chariots of Pharaoh and his host He cast into the sea, etc."
Pharaoh Threw Everything He Had into This Pursuit
Mekhilta Tractate Shirah 2:8