Sayyiduna Salamah bin al-Akwa' (may Allah be pleased with him) says: When we came to Khaybar, the Messenger of Allah (peace and blessings be upon him) saw fires burning. He (peace and blessings be upon him) asked: "What are these fires?" The Companions said: The meat of domestic donkeys is being cooked. He (peace and blessings be upon him) said: "Break the pots and pour out the meat." The narrator says: A man from among the people said: Shall we pour it out and wash the pots? He (peace and blessings be upon him) said: "Yes, wash them."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الضحايا / 19458