Joshua 8:24-25

24And it came to pass when Israel had made an end of slaying all the inhabitants of Ai in the field, in the wilderness where they pursued them, and when they all had fallen by the edge of the sword until they were consumed, that all the Israelites returned to Ai and struck it with the edge of the sword.

25So it was that all who fell that day, both men and women, were twelve thousand—all the people of Ai.