Numbers 21:34-35

And the LORD said unto Moses, Fear him not: for I have delivered him into thy hand, and all his people, and his land; and thou shalt do to him as thou didst unto Sihon king of the Amorites, which dwelt at Heshbon. So they smote him, and his sons, and all his people, until there was none left him alive: and they possessed his land.