Musnad Abu Ya'la al-Mawsili 148:78

Abu Bakr ibn Abi Shaybah narrated to us, Waki' narrated to us, from al-Hakam ibn 'Atiyyah, from Abu al-Mukhayis al-Yashkuri, from Anas ibn Malik: It was said, "O Messenger of Allah, so-and-so, your freed slave, has been martyred." He said, "Nay, for I saw upon him a cloak he had misappropriated on such-and-such a day."