Numbers 33:3-5

King James Version

³ And they departed from Rameses in the first month, on the fifteenth day of the first month; on the morrow after the passover the children of Israel went out with an high hand in the sight of all the Egyptians.

⁴ For the Egyptians buried all their firstborn, which the Lord had smitten among them: upon their gods also the Lord executed judgments.

⁵ And the children of Israel removed from Rameses, and pitched in Succoth.