Quran 43:54

Note that verses 43:51, 52, 53 and 54 explains that Pharaoh falsely convinced his people that he possessed kingship over Egypt and that the flowing rivers belong to him. In addition he injected into the minds of his people that Moses was poor, did not possess any treasures of gold, and there were no angels to accompany him; thus Pharaoh fooled his people who blindly obeyed him. This created a perfect reason for them to suffer the retribution of Allah. The two subsequent verses, 43:55 and 43:56 detail the confirmed retribution through the letters of Allah.