1 Kings 11:14-16
11:14 The Lord brought against Solomon an enemy, Hadad the Edomite, a descendant of the Edomite king.
11:15 During David’s campaign against Edom, Joab, the commander of the army, while on a mission to bury the dead, killed every male in Edom.
11:16 For six months Joab and the entire Israelite army stayed there until they had exterminated every male in Edom.