IDF sources view the two names symbolically, likening them to a "Dr. Jekyll and Mr. Hyde" duality, suggesting a true internal struggle within Syria's leader and his shifting alliances.

Some 10,000 ISIS fighters are imprisoned in the region, where the U.S.-backed Kurdish militia, known as the Syrian Democratic Forces, is charged with keeping them locked up.

A suspected ISIS leader and his sons were killed in what appeared to be the a coordinated operation between US special operations forces and Syrian government-aligned militias.

ISIS now holds "less than a single square mile" of territory in the city of Baghouz out of "an area of 34,000 square miles which they once controlled," Votel said. Syrian Democratic Forces (SDF ...