The U.S. and South Korea concluded their annual large-scale summer exercise on Thursday, capping 11 days of drills that included training on maritime infiltration, river crossings and countering weapons of mass destruction to bolster readiness against North Korean threats.

Ulchi Freedom Shield (UFS) kicked off on Aug. 18 and featured drills across land, sea, air, space, cyber and intelligence domains, according to a U.S.-ROK Combined Forces Command (CFC) press release.