Musannaf Ibn Abi Shayba 28:598

Waki’ narrated to us, he said: Sadaqah al-Dimashqi narrated to us, from Yahya ibn Yahya al-Ghassani, he said: I wrote to Umar ibn Abd al-Aziz asking him about this verse: "And fight in the way of Allah those who fight you and do not transgress. Indeed, Allah does not like transgressors." He said: So he wrote back to me that this refers to women, children, and those among them who do not set themselves up for war.