1 Chronicles 20:3

And he brought out the people that were in it, and cut them with saws, and with harrows of iron, and with axes. Even so dealt David with all the cities of the children of Ammon. And David and all the people returned to Jerusalem.

Cross-reference

1 Chronicles 19:2-5 recounts the mistreatment of David's envoys by Hanun, which led to the war that ends with the forced labor described here.

Joshua 9:23 curses the Gibeonites to be woodcutters and water carriers — a precedent for David reducing Ammonites to forced labor.

2 Samuel 12:31 gives the same account — David forces Ammonites to labor with saws, picks, and axes, confirming the parallel record.