Joshua 8:1-3

Ai Destroyed 1Then the LORD said to Joshua, “Do not be afraid; do not be discouraged. Take the whole army with you, and go up and attack Ai. For I have delivered into your hands the king of Ai, his people, his city and his land.

2You shall do to Ai and its king as you did to Jericho and its king, except that you may carry off their plunder and livestock for yourselves. Set an ambush behind the city.” 3So Joshua and the whole army moved out to attack Ai. He chose thirty thousand of his best fighting men and sent them out at night