2 Chronicles 20:23

23 For the children of Ammon and Moab stood up against the inhabitants of mount Seir, utterly to slay and destroy them: and when they had made an end of the inhabitants of Seir, every one helped to destroy another.

2 Chronicles 20:23 In-Context

21 And when he had taken counsel with the people, he appointed them that should sing unto Jehovah, and give praise in holy array, as they went out before the army, and say, Give thanks unto Jehovah; for his lovingkindness [endureth] for ever.
22 And when they began to sing and to praise, Jehovah set liers-in-wait against the children of Ammon, Moab, and mount Seir, that were come against Judah; and they were smitten.
23 For the children of Ammon and Moab stood up against the inhabitants of mount Seir, utterly to slay and destroy them: and when they had made an end of the inhabitants of Seir, every one helped to destroy another.
24 And when Judah came to the watch-tower of the wilderness, they looked upon the multitude; and, behold, they were dead bodies fallen to the earth, and there were none that escaped.
25 And when Jehoshaphat and his people came to take the spoil of them, they found among them in abundance both riches and dead bodies, and precious jewels, which they stripped off for themselves, more than they could carry away: and they were three days in taking the spoil, it was so much.
The American Standard Version is in the public domain.