Deuteronomy 20:16-17

Laws Concerning War with Canaanite Nations

20:16 As for the cities of these peoples that the Lord your God is going to give you as an inheritance, you must not allow a single living thing to survive. 20:17 Instead you must utterly annihilate them – the Hittites, Amorites, Canaanites, Perizzites, Hivites, and Jebusites – just as the Lord your God has commanded you,