Joshua 7:2-5
7:2 Joshua sent men from Jericho to Ai (which is located near Beth Aven, east of Bethel) and instructed them, “Go up and spy on the land.” So the men went up and spied on Ai.
7:3 They returned and reported to Joshua, “Don’t send the whole army. About two or three thousand men are adequate to defeat Ai. Don’t tire out the whole army, for Ai is small.”
7:4 So about three thousand men went up, but they fled from the men of Ai.
7:5 The men of Ai killed about thirty-six of them and chased them from in front of the city gate all the way to the fissures and defeated them on the steep slope. The people’s courage melted away like water.