The activists from the Solidarity for Peace and Reunification of Korea (SPARK) gathered near the presidential office in central Seoul, where the defense ministry is also headquartered, to call for peace on the Korean Peninsula.
The protesters shouted slogan of "Stop war exercise" and lifted the placards of "Stop South Korea-U.S. war exercise" and "No to South Korea-Japan alliance."
The Ulchi Freedom Shield (UFS) exercise between South Korea and the U.S., a summertime joint military exercise involving large-scale field maneuvers, was scheduled to continue until Aug. 31, according to South Korea's Joint Chiefs of Staff (JCS).
North Korean leader Kim Jong-un visited the navy to observe the test of strategic cruise missiles. The launch took place against the backdrop of a U.S. and South Korean military exercise called the Ulchi Freedom Shield, which Pyongyang sees as a rehearsal for war.… pic.twitter.com/fsWvnXorFO
The annually-held military drill this year will reportedly involve about 30 field maneuvers, compared to 13 conducted last year.
The SPARK said in a statement that the UFS exercise is a war exercise, which can turn into a nuclear war at any time, as it is the large-scale preemptive strike drill involving nuclear and advanced conventional forces from the two allies.
The civic group urged Seoul and Washington to immediately stop and abolish the UFS exercise, which can intensify the nuclear confrontation on the peninsula.
It added that the efforts for the trilateral military cooperation among the U.S., Japan and South Korea should be stopped as it can escalate regional tensions.