The operation came to light on January 18, when hundreds of police officers, led by NIS officers, conducted search raids at a number of regional offices of the Korean Confederation of Trade Unions (KCTU). Founded in the mid-1990s, the KCTU is South Korea’s second-largest labor coalition, representing over 1.1 million members. It is politically aligned with the Democratic Party of Korea (DPK), a left-of-center liberal coalition which was in government until last year. Since its establishment in 2014, the DPK has been engaged in a bitter political rivalry with the People Power Party (PPP), a conservative coalition that currently governs South Korea.

According to reports, the NIS is investigating charges that members of the KCTU formed “a clandestine organization” that engaged in protests against the United States and organized “various subversive campaigns under instructions from North Korea”. According to the NIS, the clandestine organization was led by a senior KCTU official, who was handled by clandestine operatives of North Korea’s ruling political party, the Workers’ Party of Korea (WPK). The NIS claims that the official met repeatedly with WPK operatives during trips to countries like Vietnam and Cambodia, between 2016 and last year.

On January 18, a large police force appeared to be trying to enter the KCTU headquarters in Seoul, in an attempt to arrest the trade union official, who has not been named. Video footage appeared on South Korean social media, which appeared to show a standoff between law enforcement and KCTU officials. The latter attempted to be trying to prevent the police and NIS representatives from entering the building. Eventually, the authorities were able to enter the building, while also attempting to prevent some individuals barricaded inside from leaving.

The opposition DPK has strongly condemned the NIS/police raids, calling them politically motivated and describing them as a return to the days of rightwing military rule, which South Korea experienced until 1987. The NIS remains highly controversial among left-of-center South Koreans, many of whom view it as a corrupt state entity that is politically aligned with the conservative PPP. Between 2018 and 2022, the liberal DPK government spearheaded what it described as an “anti-corruption campaign” inside the NIS.

As a result of that campaign, three former NIS directors were charged with, and eventually convicted for, secretly diverting funds from the agency’s clandestine budget in order to aid the then South Korean President, Park Geun-hye. Their apparent goal was to prevent the DPK from coming to power, fearing that the left-of-center party was too close to Pyongyang. President Prak also went to prison for accepting financial bribes from the NIS.