Musnad Ahmad 26:96

Isma'il narrated to us, Ayyub narrated to us, from Humayd ibn Hilal, from Abu Qatadah, from Yasir ibn Jabir, who said: A red wind stirred in Kufa, and a man came whose only constant saying was: "O Abdullah ibn Mas'ud, the Hour has come." He said: He was reclining, so he sat up and said: "The Hour will not be established until inheritance is not divided, and there is no rejoicing over spoils of war." He said: "An enemy will gather against the people of Islam, and the people of Islam will gather against them." Then he mentioned the hadith. He said: A caller will come to them saying that the Dajjal has appeared among their offspring. So they will cast aside what is in their hands and return. They will send ten horsemen as scouts. The Messenger of Allah (peace and blessings of Allah be upon him) said: "I surely know their names, the names of their fathers, and the colors of their horses. They are the best horsemen on the face of the earth on that day," or he said: "They are among the best horsemen on the face of the earth on that day."