The Corruption Investigation Office for High-Ranking Officials(CIO) has begun questioning President Yoon Suk Yeol, who was arrested Wednesday on suspicion of leading an insurrection.

The CIO announced in a statement that Deputy Chief Prosecutor Lee Jae-seung started the interrogation at 11 a.m. 

Yoon’s defense attorneys, all prominent former prosecutors specializing in criminal and special investigations, have been present during the questioning.

The CIO is expected to focus on key charges being considered for Yoon, including declaring martial law illegally and in violation of the Constitution; unlawfully obstructing the entrance to the National Assembly; attempting to interfere with the parliamentary vote to lift martial law by deploying police and military personnel; and attempting to unlawfully arrest opposition party leaders.

The CIO can question President Yoon for 48 hours before deciding whether to apply for a pretrial detention warrant.