Sayyiduna Salamah bin al-Akwa' (may Allah be pleased with him) narrated: On the day of Khaybar we were struck by severe hunger, and the people lit fires. The Prophet (peace and blessings be upon him) asked: "What are these fires?" The people said: For cooking the meat of domestic donkeys. He (peace and blessings be upon him) said: "Pour out what is in them, and break the pots." A man said: O Messenger of Allah, or shall we pour it out and wash them? He (peace and blessings be upon him) said: "That is also fine."
Hadith Referenceالمعجم الكبير للطبراني / باب السين / 6274