Musnad Ahmad 30:483

'Abd al-Razzaq narrated to us, Ma'mar informed us, from al-Zuhri, from Sa'id ibn al-Musayyib, from Abu Hurayrah, who said: The Prophet, peace and blessings of Allah be upon him, was asked about a mouse that falls into ghee. He said: "If it is solid, then throw it away and what is around it. And if it is liquid, then do not go near it."