1 Chronicles 19:18 (KJV)

And when the Syrians saw that they were put to the worse before Israel, they sent messengers, and drew forth the Syrians that were beyond the river: and Shophach the captain of the host of Hadarezer went before them.

And it was told David; and he gathered all Israel, and passed over Jordan, and came upon them, and set the battle in array against them. So when David had put the battle in array against the Syrians, they fought with him.

But the Syrians fled before Israel; and David slew of the Syrians seven thousand men which fought in chariots, and forty thousand footmen, and killed Shophach the captain of the host.

And when the servants of Hadarezer saw that they were put to the worse before Israel, they made peace with David, and became his servants: neither would the Syrians help the children of Ammon any more.