South Korea’s impeached President Yoon Suk Yeol was formally arrested early on Sunday, days after being apprehended at his presidential compound in Seoul. He faces possible imprisonment over his ill-fated declaration of martial law last month.

Impeached South Korean President Yoon Suk Yeol was arrested following a court ruling on allegations of rebellion tied to his December 3 martial law declaration, which caused the nation’s gravest political crisis in decades. Yoon’s supporters clashed with police outside the Seoul courthouse, leading to dozens of arrests and property damage.

The development, which followed a failed arrest attempt earlier in January, deepens the fallout from his short-lived declaration of martial law last month.