Sayyiduna Ibn Umar (may Allah be pleased with them both) narrates: During one of his military expeditions, the Messenger of Allah (peace and blessings be upon him) passed by a woman who had been killed, so he (peace and blessings be upon him) forbade the killing of women and children.
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 13359