Musnad Ahmad 33:517

Yunus narrated to us, Hammad—meaning Ibn Zayd—narrated to us, from Amr ibn Dinar, from Jabir ibn Abdullah, who said: A man from the Emigrants (Muhajirun) kicked a man from the Helpers (Ansar). The people of this one gathered, and the people of that one gathered. These said: "O for the Emigrants!" And those said: "O for the Helpers!" This reached the Prophet, peace and blessings of Allah be upon him, and he said: "Leave it, for it is foul." Then he said: "What is the matter with the call of the people of Ignorance (Jahiliyyah)? What is the matter with the call of the people of Ignorance?"