Musannaf Ibn Abi Shayba 38:142

Yahya ibn Adam narrated to us, he said: Musa ibn Qays al-Hadrami narrated to us, from Salamah ibn Kuhayl, from Zayd ibn Wahb, who said: Ali delivered a sermon to us at al-Mada'in at the bridge. He said: "It has been mentioned to me that the Kharijites will emerge from the direction of the East, among them is 'the one with the breast' (Dhu al-Thudayyah), and I do not know if they are these people or others." He said: So they set out, and they encountered one another. The Haruriyyah (Kharijites) said: "Do not speak to them as you spoke to them on the day of Harura." So he spoke to them. He said: They pierced one another with spears. Some of Ali's companions said: "Break the spearheads." He said: So they turned around and killed them, and twelve or thirteen of Ali's companions were killed. He said: "Search for him." So they searched for him and found him. He said: "By Allah, I did not lie, nor was I lied to. Work and rely [upon Allah]. Were it not that you would speak [about it], I would have informed you of what Allah has decreed for you upon the tongue of your Prophet." Then he said: "People in Yemen have testified." They said: "How is that, O Commander of the Faithful?" He said: "Allah guided them to be with us."