South Korean President Yoon Suk Yeol shocked the nation when he declared martial law and called in troops to secure the National Assembly building where parliament sits. The announcement sent citizens streaming to the streets on a cold December night to call for Yoon to resign and martial law to be lifted.

U.S. officials have expressed "grave concern" over an incident of martial law being declared this week in South Korea.

The South Korean parliament has voted to defy the country's president and immediately lift his martial law declaration. President Yoon Suk Yeol declared martial law late Tuesday, vowing to eliminate “anti-state” forces.