Police officers block access to the National Assembly compound in Seoul, Tuesday night, shortly after President Yoon Suk Yeol declared martial law. Yonhap

South Korea's news media and publications have been placed under martial law following the enactment of emergency measures at 11 p.m., Tuesday.

Under the order, all political activities, encompassing the National Assembly, local governments, and political parties have been prohibited.

The sweeping restrictions, announced by Martial Law Commander Gen. Park An-su, chief of staff of the Army, include a ban on strikes, acts of sabotage, and rallies inciting social unrest.

The commander's announcement came roughly an hour after President Yoon Suk Yeol delivered a surprise live briefing declaring emergency martial law. Yoon stated that the move is aimed at "eradicating pro-North Korean forces and protecting the constitutional order of freedom."

This marks the first declaration of martial law by a South Korean president since the May 18 pro-democracy uprising against the military government in 1980.

According to the martial law command, the emergency law also mandates that all medical professionals, including junior doctors on strike or absent from their duties, must return to work within 48 hours. Thousands of resident doctors here have been striking since February to protest against the government's medical reform plans.

Violators of the proclamations will face arrest and searches and seizures without warrants under martial law. Punishments will also be enforced in accordance with the measure.

Military authorities said steps will be implemented to minimize the disruption to ordinary citizens. However, they also issued a warning that those labeled as "anti-state forces" or individuals attempting to undermine the national system will not be covered by these provisions.