Musnad Ahmad 403:14

Abdullah ibn Ahmad said: Ishaq ibn Mansur informed us, he said: Abd al-Razzaq informed us, he said: Ma'mar informed us, from al-Zuhri, from Ubayd Allah ibn Abd Allah, from Ibn Abbas, from al-Sa'b ibn Jaththama, who said: I said: "O Messenger of Allah, we strike the children of the polytheists during the night raids." He said: "They are of them."