Musnad Ahmad 32:2105

'Affan narrated to us, Hammad narrated to us, he said: Thabit informed us, from Anas, that Umm Sulaym was with Abu Talha on the day of Hunayn, and Umm Sulaym had a dagger with her. Abu Talha said: "What is this with you, O Umm Sulaym?" Umm Sulaym said: "I took it so that if any of the disbelievers approach me, I will rip open his belly with it." Abu Talha said: "O Prophet of Allah, do you not hear what Umm Sulaym is saying? She says such and such." She said: "O Messenger of Allah, kill those who are left behind among the Tulaqa (those freed at the conquest of Mecca), for they fled from you, O Messenger of Allah." He said: "O Umm Sulaym, indeed Allah has sufficed us and done well."