Musnad Ahmad 529:10

Haywah ibn Shurayh narrated to us, Baqiyyah narrated to me, Buhayr ibn Sa’d narrated to me, from Khalid ibn Ma’dan, from ‘Utbah ibn ‘Abd, that he said: A man said: "O Messenger of Allah, curse the people of Yemen, for their might is severe, their numbers are many, and their fortresses are fortified." He said: "No." Then the Messenger of Allah, peace and blessings of Allah be upon him, cursed the non-Arabs (al-A’jamiyyin). And the Messenger of Allah, peace and blessings of Allah be upon him, said: "When they pass by you, driving their women and carrying their children upon their shoulders, then they are of me, and I am of them."