Musnad Ahmad 27:1288

Yahya ibn Ishaq narrated to us, Aban ibn Yazid narrated to us, from Yahya ibn Abi Kathir, from Abu Qilabah, from Salim, from his father, that the Messenger of Allah (peace and blessings of Allah be upon him) said: "A fire will emerge from the direction of Hadhramaut that will gather the people." We said: "What do you command us, O Messenger of Allah?" He said: "You must go to Ash-Sham."