Musannaf Ibn Abi Shayba 35:132

36180. Abd al-Rahim narrated to us, Ibn Abi Arubah narrated to us, from Qatadah, from al-Hasan, from the Prophet (may Allah bless him and grant him peace), who said: "Whoever kills his slave, we kill him; and whoever mutilates his slave, we mutilate him." And he mentioned that Abu Hanifah said: "He is not killed for him."