1 Chronicles 19:7-9

7So they hired 32,000 chariots along with the king of Maacah and his people, who came and camped before Medeba. The children of Ammon also assembled from their cities and moved out to the battle.

8On hearing this, David sent Joab and the entire army of mighty men.

9The children of Ammon came out and took up battle formation at the city gate, while the kings who had come were by themselves in the field.