Musannaf Ibn Abi Shayba 18:1333

Abu Bakr narrated to us, he said: Abu Bakr ibn Ayyash narrated to us, from Asim, he said: Adi ibn Artah, the judge of Basra, wrote to Umar ibn Abd al-Aziz: "I have found a slain person in the butchers' market." He said: "As for the slain person, his blood money is from the public treasury (Bayt al-Mal)."