Musnad Abu Ya'la al-Mawsili 3:231

Ishaq narrated to us, Sufyan narrated to us, from Abd al-Malik ibn A'yan, from Abu Harb ibn Abi al-Aswad al-Du'ali, from his father, from Ali, who said: Abdullah ibn Salam came to me while I had placed my foot in the stirrup. He said to me, "Do not go to Iraq, for I fear that the 'fly of the sword' (i.e., the edge of the sword) will strike you there." Ali said, "By Allah, the Messenger of Allah (peace and blessings of Allah be upon him) had indeed informed me of it." Abu al-Aswad said, "I have never seen a warrior like today, informing about himself with this."