No, they fought on the side of the Israelites. Mighty men is the term used in the old testament to describe King David's elite task force. They were extremelly skilled at war using a variety of weapons, and some of them were ambidextrous. Just do a Google search or read 2 Samuel 10:7, 2 Samuel 23, 1 Chronicles chapters 11, 12, and 19, 28 (this chapter mentions Solomon's temple too)