Joshua 8:21-22

21When Joshua and all Israel saw that the [men in] ambush had taken the city and that the smoke of the city was ascending, they turned back and struck down the men of Ai.

22Then the others came out of the city to confront the men of Ai [as they returned], so that they were trapped in the midst of Israel, some on this side and some on that side; then Israel struck them until none of them survived or escaped.