Musannaf Ibn Abi Shayba 28:236

Abu Mu'awiyah narrated to us, from al-A'mash, from Abu 'Amr al-Shaybani, from 'Ali, that al-Mustawrid al-'Ijli was brought to him, and he had apostatized. He offered Islam to him, but he refused. He said: So he killed him and placed his inheritance among his Muslim heirs.