Musnad Ahmad 947:3

Muhammad ibn al-Qasim narrated to us, from al-Awza'i, from Hassan ibn 'Atiyyah, from Abu Waqid al-Laythi, who said: I said, "O Messenger of Allah, we are in a land where we are afflicted by famine, so what is permissible for us of dead meat?" He said: "If you do not have morning milk, and you do not have evening milk, and you do not have any gathered herbs, then deal with it [i.e., eat it]."