1 Chronicles 18:12 in the King James Version
Moreover Abishai the son of Zeruiah slew of the Edomites in the valley of salt eighteen thousand.
Context
11 King David also dedicated these to the LORD, with the silver and the gold that he carried away from all the nations: from Edom, from Moab, from the children of Ammon, from the Philistines, and from Amalek.
12 Moreover Abishai the son of Zeruiah struck eighteen thousand of the Edomites in the Valley of Salt.
13 He put garrisons in Edom; and all the Edomites became servants to David. The LORD gave victory to David wherever he went.