What led to the impeachment proceedings against South Korean President Yoon?

• On Thursday, a motion for impeachment was presented to the National Assembly's plenary session, leading to a full-house vote this week, as reported by local news.
• If Yoon's impeachment is approved by parliament, it proceeds to the Constitutional Court for a final decision on whether to validate or reject the impeachment.

Yoon Suk Yeol, the South Korean President, is facing impeachment by parliament due to a series of surprising actions that led to the declaration of martial law in the country for the first time in nearly 50 years.

On Wednesday, the Democratic Party of South Korea, along with other parties, filed articles of impeachment against the government, citing an "unconstitutional and illegal declaration of martial law" as the reason.

On Thursday, a motion for impeachment was presented to the National Assembly's plenary session, leading to a full-house vote this week, as reported by local news.

With a majority of control in parliament, the DPK and members of smaller opposition parties hold 192 out of 300 seats. As a result, the coalition may only require eight additional votes to achieve a two-thirds majority and impeach the leader.

If Yoon's impeachment is approved by parliament, it will proceed to the Constitutional Court for a final decision on whether to confirm or reject the impeachment.

The leader of Yoon's ruling party announced on Thursday that he intends to prevent the impeachment motion from passing by uniting his party.

Yoon's office has consistently argued that his call for martial law was constitutional in emails sent to NBC News.

The chief of staff and all senior presidential secretaries, as well as Defense Minister Kim Yong-hyun, have reportedly resigned.

How did we get here?

On Tuesday night, Yoon announced martial law through a late-night TV address, causing six hours of turmoil in South Korea and mobilizing the country's military forces.

In an address on the country's YTN news channel, he stated that he was taking this action "to safeguard the constitutional order," alleging that opposition parties were supporting North Korea and holding sway over parliament.

After Yoon's announcement, a martial law proclamation was issued, banning all political activities, including protests, strikes, and the functioning of the National Assembly.

The country's striking doctors were ordered to return to work within 48 hours under Martial Law Command, which also declared all media.

Immediately after Yoon's address was announced, there was a nationwide backlash from lawmakers, citizens, and unions. Meanwhile, defiant members of parliament rushed to the National Assembly building for a delegation.

A resolution demanding the lifting of martial law was passed by Parliament with 190 of its 300 members present, as protests occurred outside the building.

On Wednesday, Yoon appeared on national television and retracted his martial law declaration amid increasing pressure.

"He acknowledged the National Assembly's decision to dissolve and lift martial law, but also urged them to stop engaging in "repeated acts of impeachment, legislative manipulation, and budgetary sabotage that hinder the country's operations.""

— NBC's Stella Kim and Jennifer Jett contributed to this report