Musannaf Ibn Abi Shayba 38:139

Yazid ibn Harun narrated to us, he said: Hammad ibn Salamah informed us, from Sa'id ibn Jahman, he said: The Khawarij had invited me until I almost entered among them. Then the sister of Abu Bilal saw in a dream as if she saw Abu Bilal, and he was disheveled. I said, "O my brother, what is your state?" He said, "O my sister, your state." He said, "He said: We have been made, after you, the dogs of the people of the Fire."