Musannaf Ibn Abi Shayba 18:902

Abu Bakr narrated to us, he said: Jarir narrated to us, from Mughira, from al-Harith, regarding a man who strikes a man. He said: If the witnesses testify that he struck him, and he did not cease to be ill from his striking until he died, the blood money (diyah) is binding upon him. If it was intentional, then it is retaliation (qisas), and if it was a mistake, then the blood money is upon the paternal relatives (aqilah).