Musnad Abu Ya'la al-Mawsili 128:9

Abu Khaythama narrated to us, Ibn 'Uyaynah narrated to us, from Qasim al-Rahhal, from Anas ibn Malik, who said: The Messenger of Allah (may Allah bless him and grant him peace) entered a ruin belonging to the Banu al-Najjar to relieve himself. He came out to us alarmed and said: "Were it not that you would not bury one another, I would have asked Allah to let you hear from the punishment of the grave what I hear."