South Korean prosecutors indicted the impeached President Yoon Suk Yeol on insurrection charges over his declaration of martial law, a move that plunged the country into political turmoil.

The charges are unprecedented for a South Korean president, and if convicted, Yoon Suk Yeol could face years in prison for his shock martial-law decree, which sought to ban political and parliamentary activity and control the media.

South Korea’s impeached president has denied that he ordered the military to drag lawmakers out of the National Assembly to prevent them from voting to reject his martial law decree last month, as he appeared for the first time before the Constitutional Court that will determine his fate.