Exodus 1:11-14

So the Egyptians made the Israelites their slaves. They appointed brutal slave drivers over them, hoping to wear them down with crushing labor. They forced them to build the cities of Pithom and Rameses as supply centers for the king. But the more the Egyptians oppressed them, the more the Israelites multiplied and spread, and the more alarmed the Egyptians became. So the Egyptians worked the people of Israel without mercy. They made their lives bitter, forcing them to mix mortar and make bricks and do all the work in the fields. They were ruthless in all their demands.