South Korean police conducted a raid on the office of President Yoon Suk Yeol on Wednesday, escalating a high-profile investigation into his failed attempt to impose martial law. A presidential security official confirmed the operation, while the national police agency declined to comment immediately.

According to Yonhap News Agency, investigators presented a search warrant identifying President Yoon as the subject of the inquiry. This unprecedented move deepens the constitutional crisis engulfing Asia's fourth-largest economy and a key U.S. ally.

The probe centers on the surprise December 3 martial law declaration, which led to allegations of insurrection against top military and police officials. Earlier on Wednesday, the national police chief was arrested, joining other high-ranking officials implicated in the scandal.

Kim Yong-hyun, a former defense minister and a close ally of Yoon, also faces insurrection charges. Kim reportedly attempted suicide while in detention but is now under observation and out of immediate danger, a Justice Ministry official told a parliamentary hearing.

President Yoon himself is now under criminal investigation for alleged insurrection and has been banned from leaving the country. However, authorities have not yet arrested or questioned him.

The crisis has shaken South Korea’s political landscape, with Yoon’s martial law declaration sparking widespread criticism and a judicial reckoning that could redefine his presidency.