SEOUL -- South Korea's ousted president Yoon Suk-yeol on Monday attended the second hearing of his criminal trial over insurrection charges.

Yoon entered a courtroom of the Seoul Central District Court around 9:57 am local time (0057 GMT) after arriving at the court through its underground parking lot.

He was photographed and filmed in the defendant's seat by photographers and cameramen, who left the courtroom before the hearing was formally launched.

On April 4, the constitutional court upheld a motion by the parliament to impeach Yoon over his short-lived martial law imposition. With the court's decision, the conservative leader officially lost all presidential power.

Yoon declared an emergency martial law on the night of Dec 3 last year, but it was revoked by the opposition-led National Assembly hours later.

The impeachment motion against Yoon was passed in the parliament on Dec 14 last year.

Yoon was apprehended in the presidential office on Jan 15 and was indicted under detention on Jan 26 as a suspected ringleader of insurrection.

If convicted of being the insurrection ringleader, Yoon could face the death penalty or life imprisonment.

He was released on March 8 as the prosecution decided not to appeal against the court's release approval.