1. The verb "completely destroyed" and "destroying" in this verse is cherem, which refers to a particular kind of destruction in which everything that could be destroyed, including men, women and children, were to be annihilated, and what could not be, such as gold and silver were set aside for Yahweh. No portion of the loot could be kept by any person. Contravention of this rule subjects the culprit, e.g., Achan (Jos 7), and his entire family to the cherem. Read More
2. The earlier account in Num 21:33-35 is equally laconic and opaque.