Jeremiah 41:9-12

9Now the cistern into which Ishmael had thrown all the corpses of the men whom he had killed along with Gedaliah was the one which King Asa [of Judah] had made [about three hundred years earlier] on account of King Baasha of Israel [believing that Baasha would lay siege to Mizpah]. Ishmael the son of Nethaniah filled it with [the bodies of] those who were killed.

10Then Ishmael took captive all the rest of the people who were in Mizpah—even the king’s daughters (ladies of the court) and all the people who remained in Mizpah, whom Nebuzaradan the captain of the bodyguard had put under the charge of Gedaliah the son of Ahikam. Ishmael the son of Nethaniah took them captive and crossed over [the Jordan] to [meet his allies] the Ammonites.

11But when Johanan the son of Kareah and all the commanders of the forces that were with him heard of the murderous behavior of Ishmael the son of Nethaniah,

12they took all their men and went to fight with Ishmael the son of Nethaniah and found him by the great pool in Gibeon.