South Korean President Yoon Suk-yeol oversaw the grand finale of live-fire “annihilation” exercises with the U.S. on Thursday, hours after pledging to “overwhelmingly” respond to North Korean aggression without “a moment's hesitation.”

The field training and live-fire drill featured some 2,500 soldiers and “610 state-of-the-art weapons” and was modeled on a scenario of repelling DPRK invasion and conducting a counterattack, according to the presidential office.