Jeremiah 41:9-13

Now as for the cistern where Ishmael had thrown all the bodies of the men whom he had struck and killed because of Gedaliah, it was the one that King Asa had constructed on account of Baasha, king of Israel; Ishmael the son of Nethaniah filled it with the dead.

Then Ishmael took captive all the remnant of the people who were in Mizpah, the king’s daughters and all the people who were left in Mizpah, whom Nebuzaradan the captain of the bodyguard had put in the custody of Gedaliah the son of Ahikam. Ishmael the son of Nethaniah took them captive and proceeded to cross over to the sons of Ammon. Johanan Rescues the People

But Johanan the son of Kareah and all the commanders of the forces that were with him heard about all the evil that Ishmael the son of Nethaniah had done.

So they took all the men and went to fight with Ishmael the son of Nethaniah and they found him by the large pool that is in Gibeon.

Now as soon as all the people who were with Ishmael saw Johanan the son of Kareah and all the commanders of the forces that were with him, they were joyful.