After Israel's defeat at Ai, what did Joshua do before the ark of the LORD until evening?

Answer: Fell facedown with torn clothes

Joshua tore his clothes and fell facedown before the ark until evening; he and the elders of Israel sprinkled dust on their heads.

“Then Joshua tore his clothes and fell facedown before the ark of the LORD until evening, as did the elders of Israel; and they all sprinkled dust on their heads.”— Joshua 7:6 (BSB)