Musannaf Ibn Abi Shayba 36:253

Khalid ibn Makhlad narrated to us, he said: Abd al-Rahman ibn Abd al-Aziz narrated to us, he said: al-Zuhri narrated to us, from Abd al-Rahman ibn Ka'b ibn Malik, from his father, that the Messenger of Allah (may Allah bless him and grant him peace) said on the day of Uhud: "Who saw the killing of Hamza?" A man said: "I am; I saw his killing." He said: "Then go and show him to us." He went out until he stood over Hamza and saw that his stomach had been slit open and he had been mutilated. He said: "O Messenger of Allah, he has been mutilated, by Allah." The Messenger of Allah (may Allah bless him and grant him peace) disliked looking at him. He stood among the slain and said: "I am a witness over these people. Wrap them in their blood, for there is no wounded person who is wounded but that his wound will bleed on the Day of Resurrection; its color will be the color of blood, and its scent will be the scent of musk. Present the one among the people who knew the most Quran, and place him in the *lahd* (niche of the grave)."