Musnad Ahmad 26:83

Abu Mu'awiyah narrated to us, Al-A'mash narrated to us, from Abdullah ibn Murrah, from Masruq, from Abdullah, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "No soul is killed unjustly, except that there is upon the first son of Adam a share of its blood, because he was the first to establish the practice of killing."