Following the assassination of Gedaliah, Ishmael son of Nethaniah seizes full control of Mizpah. Rather than slaughtering the entire community, he targets only the fighting men. The remaining civilians, including women and children, are spared from death but taken as his captives [רד״ק].
This captured population is made up of two distinct groups. The first consists of refugees who had previously fled to neighboring countries and recently returned to Mizpah on their own. The second group comprises the original local population, whom the Babylonian commander Nebuzaradan had specifically placed under Gedaliah's protection [מלבי״ם, מצודת דוד, ביאור שטיינזלץ].
Standing out prominently among these prisoners are the royal daughters. During the Babylonian conquest, Nebuzaradan chose not to exile them to Babylon, instead leaving them behind with the poorest citizens. There is some debate regarding their exact lineage; they are often identified as the daughters of King Zedekiah [ביאור שטיינזלץ], though it is also possible they were the children of earlier kings such as Jehoiachin or Jehoiakim [רד״ק]. Regardless of their specific parentage, Ishmael takes them captive, recognizing their immense value and high social status [ביאור שטיינזלץ].
With his prisoners secured, Ishmael sets out to cross the Jordan River and relocate to the territory of the Ammonites [מצודת דוד]. This journey exposes the true motive behind his violent campaign. Ishmael is acting as an agent of the Ammonite king, whose ultimate goal is to incite chaos and completely erase any remaining trace of Babylonian authority in the region [ביאור שטיינזלץ].