Musannaf Ibn Abi Shayba 37:341

Abdullah ibn Numayr narrated to us, he said: Isma'il ibn Abi Khalid narrated to us, from Zayd ibn Wahb, who said: Hudhayfah said: "Two factions will fight in this low-lying land (al-ghait), and I do not care in which of the two I recognize you." A man said to him: "Are these people in Paradise or in the Fire?" He said: "That is what I am telling you." He said regarding their slain: "They are the slain of Jahiliyyah (pre-Islamic ignorance)."