1 Chronicles 20:1-3

In the spring, the time of year when kings normally went out to battle, Joab led out the army of Israel. But David stayed in Jerusalem. The army of Israel destroyed the land of Ammon and went to the city of Rabbah and attacked it. David took the crown off the head of their king, and had it placed on his own head. That gold crown weighed about seventy-five pounds, and it had valuable gems in it. And David took many valuable things from the city. He also brought out the people of the city and forced them to work with saws, iron picks, and axes. David did this to all the Ammonite cities. Then David and all his army returned to Jerusalem.