2 Chronicles 25:12 (KJV)

Then Amaziah separated them, to wit, the army that was come to him out of Ephraim, to go home again: wherefore their anger was greatly kindled against Judah, and they returned home in great anger.

And Amaziah strengthened himself, and led forth his people, and went to the valley of salt, and smote of the children of Seir ten thousand.

And other ten thousand left alive did the children of Judah carry away captive, and brought them unto the top of the rock, and cast them down from the top of the rock, that they all were broken in pieces.

But the soldiers of the army which Amaziah sent back, that they should not go with him to battle, fell upon the cities of Judah, from Samaria even unto Beth–horon, and smote three thousand of them, and took much spoil.

Now it came to pass, after that Amaziah was come from the slaughter of the Edomites, that he brought the gods of the children of Seir, and set them up to be his gods, and bowed down himself before them, and burned incense unto them.