Musnad Ahmad 26:542

Yahya narrated to us, from Sufyan, Sulayman narrated to us, from Abdullah ibn Murrah, from Masruq, from Abdullah, from the Prophet (peace and blessings of Allah be upon him), who said: "No soul is killed unjustly, except that there is upon the son of Adam a share of its blood, for he was the first to establish the practice of killing."