Exodus 9:7-9

Amplified Bible

⁷ Then Pharaoh sent [men to investigate], and not even one of the livestock of the Israelites had died. But the heart of Pharaoh was hardened [and his mind was firmly set], and he did not let the people go.

The Plague of Boils

⁸ Then the Lord said to Moses and Aaron, “Take handfuls of soot from the brick kiln, and let Moses throw it toward the sky in the sight of Pharaoh. ⁹ It will become fine dust over the entire land of Egypt, and it will become boils breaking out in sores on man and animal in all the land [occupied by the Egyptians].”