It is narrated from Sayyiduna Sa'b bin Jaththamah (may Allah be pleased with him) that he said: O Messenger of Allah, we attack a settlement of the polytheists at night where their women and children are with them, and we kill them too (so what is the ruling)? He (peace and blessings be upon him) said: "They are of them."
Hadith Referenceالمعجم الكبير للطبراني / باب الصاد / 7415