High-tech new drones and massive nuclear missiles may have stolen the show during North Korea’s latest military parade, but experts say a new unit that debuted under the radar at the same event could have even more troubling implications for inter-Korean tensions — an amphibious assault battalion tasked with “mopping up” South Korean “pirates” in the Yellow Sea.

During state media’s coverage of the July 27 military parade, a unit of soldiers outfitted like marines and covered in camouflage face paint goose-stepped through Kim Il Sung Square, carrying what appeared to be AK-74 assault rifles equipped with grenade launchers.