Musannaf Ibn Abi Shayba 28:1001

Waki’ narrated to us, he said: Al-Hakam ibn ‘Atiyyah narrated to us, from Abu al-Mukhays al-Yashkuri, he said: I heard Anas ibn Malik saying: It was said, "O Messenger of Allah, so-and-so, your freed slave, has been martyred." He said: "Not at all. I saw upon him a cloak that he had misappropriated from the spoils of war."