For the Egyptians were burying all their firstborn, whom the LORD had killed among them. Also on their gods the LORD had executed judgments.
Numbers 33:4
Surrounding context
33:3 They departed from Rameses in the first month, on the fifteenth day of the first month; on the day after the Passover the children of Israel went out with boldness in the sight of all the Egyptians.
33:4 For the Egyptians were burying all their firstborn, whom the LORD had killed among them. Also on their gods the LORD had executed judgments.
33:5 Then the children of Israel moved from Rameses and camped at Succoth.