2 Samuel 10:6-8

6When the Ammonites realized they had become repulsive to David, they hired twenty thousand foot soldiers from the Arameans of Beth-rehob and Zobah, one thousand men from the king of Maacah, and twelve thousand men from Tob.

7David heard about it and sent Joab and all the elite troops.

8The Ammonites marched out and lined up in battle formation at the entrance to the city gate while the Arameans of Zobah and Rehob and the men of Tob and Maacah were in the field by themselves.