Deuteronomy 20:13-16

13and when Jehovah thy 1God delivereth it into thy hand, thou shalt smite every male thereof with the edge of the sword:

14only the women, and the little ones, and the cattle, and all that shall be in the city, all the spoil thereof, shalt thou take as booty for thyself; and thou shalt eat the spoil of thine enemies, which Jehovah thy 2God giveth thee

15Thus shalt thou do unto all the cities that are very far off from thee, which are not of the cities of these nations.

16But of the cities of these peoples which Jehovah thy 3God giveth thee for an inheritance, thou shalt save alive nothing that breatheth,