Military sources said on Friday that the Marine Corps' Yeonpyeong and Baengnyeong units are scheduled to conduct live-fire drills in response to North Korea's provocation.

The exercise is a retaliatory measure to the firing of some 200 artillery shells off the North's west coast toward South Korea’s Yeonpyeong Island in the morning.

The South Korean military says it is tracking and monitoring developments in close cooperation with the U.S.  and vowed to respond to the regime’s provocations.

The quick response comes as President Yoon Suk Yeol last week called on the military to "retaliate first, report later" in responding to the North's hostile acts.

This marks the first time in 13 months that North Korea fired artillery towards South Korea, with the last such provocation coming on December 6, 2022, when it conducted live fire drills in the maritime buffer zone around the Goseong and Geumgang areas of Gangwon Province.