2 Chronicles 20:23

For the children of Ammon and Moab stood up against the
inhabitants of Mount Seir
Supposing that they had acted a treacherous part by them, and took on the side of their enemies: utterly to slay and destroy them;
as they did: and when they had made an end of the inhabitants of Seir;
so that there were none left of them: everyone helped to destroy one another;
in their confusion mistook one another, either for Edomites or Jews, like the Midianites in the times of Gideon.