Musnad Abu Ya'la al-Mawsili 130:55

Muhammad ibn Abi Bakr narrated to us, Mubarak narrated to us, from Abd al-Aziz, from Anas—I think he said from the Prophet (peace be upon him)—he said: "Groups of people will come to my cistern, then they will be pulled away from me. I will say: 'O Lord, my companions!' It will be said: 'Indeed, you do not know what they innovated after you.'"