Carrying signs and candles and blowing horns, people packed a boulevard in front of an old palace gate that has been the center of massive but peaceful protests in recent weeks. Marches were planned near Seoul 's presidential palace and the Constitutional Court.
Park 's supporters rallied in nearby streets, surrounded by thick lines of police.
The court has up to six months to decide whether Park should permanently step down over a corruption scandal or be reinstated. The judges said Friday that Park cannot be forced to testify in the impeachment trial as it enters its argument phase next week, ABC News reported.
Protest organizers estimate that nearly 9 million people took part in anti-Park rallies nationwide in the previous nine Saturdays. The historically biggest protest movement in the country pushed lawmakers to vote for Park 's impeachment on Dec. 9.
State prosecutors have accused Park of colluding with a longtime confidante to extort money and favors from the country's largest companies and allowing the friend to manipulate her administration. Park has apologized for putting faith in her jailed friend, Choi Soon-sil, but has denied any legal wrongdoing.
"Choi Soon-sil has shown us that our democracy was shattered," said Lee Hae-jin, who protested for the 10th consecutive Saturday in Seoul , carrying a large South Korean flag and wearing black traditional hanbok and a black dance mask that he said was a commentary on the state of the country's democracy.
"I hope in 2017 we will see our democracy repaired," Lee said.
State prosecutors have now handed over the investigation to a special prosecution team, which has been focusing on proving bribery suspicions between Park and the Samsung Group. The business giant is suspected of sponsoring Choi in exchange for government favors.
On Saturday, investigators questioned Moon Hyung-pyo, the country's arrested former health minister, over allegations that he forced the National Pension Service last year to support a merger between two Samsung affiliates last year.