bestial -
resembling a beast; showing lack of human sensibility; "beastly desires"; "a bestial nature"; "brute force"; "a dull and brutish man"; "bestial treatment of prisoners"
inhumane lacking and reflecting lack of pity or compassion; "humans are innately inhumane; this explains much of the misery and suffering in the world"; "biological weapons are considered too inhumane to be used"
