Musnad Ahmad 1007:51

I read to Abd al-Rahman ibn Mahdi: Malik, from Abu al-Nadr, the freed slave of Umar ibn Ubayd Allah, from Nafi, the freed slave of Abu Qatada al-Ansari, from Abu Qatada, that he was with the Messenger of Allah (may Allah bless him and grant him peace). When they were on some part of the road to Makkah, he stayed behind with some companions of his who were in the state of ihram, while he was not in the state of ihram. He saw a wild donkey, so he mounted his horse and asked his companions to hand him his whip, but they refused. He asked them for his spear, but they refused, so he took it himself. Then he charged at the donkey and killed it. Some of the companions of the Prophet (may Allah bless him and grant him peace) ate of it, while others refused. When they caught up with the Messenger of Allah (may Allah bless him and grant him peace), they asked him about that. He said: "It is merely food that Allah has fed you."