Police on Wednesday exercised the first order to disperse a massive downtown rally led by the Korean Confederation of Trade Unions, one of the biggest umbrella labor unions in South Korea, taking a hard-line stance as instructed by President Yoon Suk Yeol.

The order was issued concerning unionized workers marching from the presidential office in Yongsan in central Seoul to the Korean National Police Agency's headquarters in Seodaemun-gu, demanding Yoon resign for "oppressing labor rights," as well as oppression of the freedom of assembly.

Although police warned of the possible use of "capsaicin sprays," no physical conflict had taken place as of press time. Police have not used capsaicin sprays to disperse protesters since March 2017.

According to the KCTU, about 20,000 members participated in the rally.

More than 120 police units and 12,000 officers were deployed across the country to control the protests, warning repeatedly that they would respond to illegal rallies in accordance with the law and arrest those who led them.

Police recently conducted training to disperse illegal rallies nationwide, and have offered promotions to police officers who respond promptly at the scene.

"One year after the inauguration of the Yoon Suk Yeol administration, Korea's democracy has been destroyed and the clock of history flowed back to the past and returned to dictatorship," said Han Sung-kyu, vice chairman of the KCTU.

“The humiliating diplomacy toward Japan has exonerated the history of aggression, and the hostile policy against North Korea is driving the Korean Peninsula into a warlike atmosphere. Now, the regime is trying not to recognize even the basic rights of the people,” Han said, citing the government’s oppression of union protests.

Ahead of the rally, KNPA Commissioner General Yoon Hee-keun warned that police would firmly control the protestors, citing possible use of the capsaicin sprays whenever illegal actions are detected during the rally.

"I can't agree with the claim that (the use of capsaicin sprays) is hard-line suppression," the commissioner general added.