Musannaf Ibn Abi Shayba 16:357

Abu Bakr narrated to us, he said: Waki’ narrated to us, from Sufyan, from al-Hasan ibn ‘Amr, from Fudayl, from Ibrahim, he said: There is no harm in [eating] the eel. This is only something they narrate from Ali, may Allah have mercy on him, in the scrolls.