Musnad Ahmad 30:1656

Al-Khuza'i Abu Salamah narrated to us, he said: 'Abdullah bin Ja'far narrated to us, from 'Uthman bin Muhammad al-Akhnasi, from al-Maqburi, from Abu Hurairah, he said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Whoever is appointed as a judge among the people has been slaughtered without a knife." It was narrated to us after that by al-Khuza'i, he said: 'Abdullah bin Ja'far informed us, he said: 'Uthman bin Muhammad informed us, from al-A'raj and al-Maqburi, from Abu Hurairah.