Musnad Abu Ya'la al-Mawsili 106:74

Muhammad narrated to us, Muhammad narrated to us, Shu'bah narrated to us, from Abu Ishaq, who said: I heard al-Bara'. A man from Qays asked him, saying: "Did you flee from the Messenger of Allah, may Allah bless him and grant him peace, on the day of Hunayn?" Al-Bara' said: "But the Messenger of Allah did not flee. The Hawazin were a people of archers, and when we charged at them, we rushed toward the spoils, so they met us with arrows. I saw the Messenger of Allah, may Allah bless him and grant him peace, on his white mule, and Abu Sufyan ibn al-Harith was holding its bridle, while he was saying: 'I am the Prophet, there is no lie; I am the son of 'Abd al-Muttalib.'"