SEOUL — South Korea's President Yoon Suk-yeol refused to appear for fresh questioning by investigators on Thursday, a day after his arrest over a failed martial law declaration.

South Korea looks set for a dramatic political showdown this week as impeachment proceedings kick off against suspended President Yoon Suk Yeol, who remains holed up in his fortified residence evading arrest for a separate criminal investigation.

Yoon’s detention, after a tense standoff outside the presidential residence, marks the latest chapter in a bewildering series of events since his martial law decree.