II Kings 25:23, 25

Now when all the captains of the armies, they and their men, heard that the king of Babylon had made Gedaliah governor, they came to Gedaliah at Mizpah—Ishmael the son of Nethaniah, Johanan the son of Careah, Seraiah the son of Tanhumeth the Netophathite, and Jaazaniah the son of a Maachathite, they and their men.

But it happened in the seventh month that Ishmael the son of Nethaniah, the son of Elishama, of the royal family, came with ten men and struck and killed Gedaliah, the Jews, as well as the Chaldeans who were with him at Mizpah.