South Korean police prepare for 'worst-case scenarios' ahead of Yoon impeachment ruling

Police will be out in force, and subway stations and at least one school will be closed over safety concerns when South Korea's Constitutional Court rules whether to oust or reinstate impeached President Yoon Suk Yeol.

Yoon's political fate hangs in the balance after his short-lived martial law decree on December 3 led to his impeachment and separate criminal charges of insurrection.

The impeachment ruling is expected to come as soon as this week, and both supporters and opponents of Yoon are expected to turn out in large numbers, with recent protests gathering tens of thousands.

"We are setting up plans considering the worst-case scenarios," Lee Ho-young, Acting Commissioner General of the National Police Agency, told reporters.

Police officers can use pepper spray or batons in case of violence similar to what happened during a rampage by Yoon supporters on a court building in January, Lee added.

On the day of the ruling, a subway station near the Constitutional Court will be closed, and trains might not stop at other subway stations where large rallies are expected, the Seoul Metro said.

The Seoul Metropolitan Office of Education sent out letters in late February advising six schools near the court to take safety measures, including closing down on the ruling day, Kim Eun-mi, an official at the education office, told Reuters.

One school decided to close for the day, Kim said.

During the court hearings so far, rings of police officers and vehicles have surrounded gatherings of thousands of Yoon supporters.

"Security has to be tighter than ever, as you can imagine how precarious this situation can get," a police official told Reuters, speaking on condition of anonymity because of the sensitivity of the matter. "We have to be on alert at the highest level, like when the Constitutional Court handed down the ruling on President Park Geun-hye."

Park was impeached over corruption allegations and removed from office by the court in March 2017. At least three people died and dozens were hurt during demonstrations after that ruling.

Police also may shut down gas stations near the court for the day of Yoon's impeachment ruling, the official said.

On Sunday, a day after Yoon returned home, thousands of Yoon supporters gathered around the residence to protest the impeachment, surrounded by beefed-up police security.

Over the weekend, police parked buses along main roads and set up some checkpoints around his residence to limit access.