American Marconi Wireless News - Protesters storm S. Korea court after president's detention extended

Tens of thousands of people had gathered outside the Seoul Western District Court on Saturday in a show of support for Yoon, who became South Korea's first sitting head of state to be arrested in a dawn raid this week.

After the court extended his detention around 3:00 am (1800 GMT Saturday), the president's supporters smashed windows and doors as they rushed inside the building.

AFP journalists saw hundreds of police officers charge into the court, with the force arresting dozens and denouncing an "intolerable illegal and violent incident".

The incident is the latest episode in South Korea's spiralling political crisis since December 3, when Yoon declared martial law and dispatched troops to parliament.

His attempt to suspend civilian rule lasted just six hours after lawmakers defied soldiers to vote it down. They later impeached the president, suspending him from duty.

Yoon has vowed to "fight to the end" despite facing a Constitutional Court ruling on his impeachment and a criminal probe on insurrection charges that has seen him detained.

In announcing investigators could hold Yoon for a further 20 days, the Seoul court told AFP there were concerns he could destroy evidence if released.

The president thanked his supporters -- including evangelical Christians and right-wing YouTubers -- for their "passionate patriotism" in a message through his lawyers Friday.

His backers have claimed Yoon was justified in imposing martial law due to election fraud in legislative polls won last year by the opposition, for which they present no evidence.

They frequently wave American flags and have adopted the "stop the steal" rhetoric associated with US president-elect Donald Trump, whose supporters stormed Washington's Capitol to try to overturn his earlier election defeat.

After the Seoul court incident, acting police chief Lee Ho-young said the force would "thoroughly investigate right-wing YouTubers if they were involved in this violent break-in".

- 'Create burdens' -

Yoon's lawyer Seok Dong-hyeon slammed the court decision, while also warning the president's supporters not to escalate the situation.

"This is likely not what President Yoon desires," he said in a statement, adding that violence could also "create burdens" for the president's future trials.

Yoo Jung-hoon, a lawyer and political columnist, said attacking a court was "unprecedented" in South Korea and those involved would likely face jail time.

The judge was expected to keep the president in prison "given the myriad evidence supporting the insurrection charges", Yoo told AFP.

"The court also placed significant weight on Yoon's attempts to destroy evidence" as a head of state, he added.

With Yoon back behind bars after his court appearance on Saturday, prosecutors are due to formalise a criminal indictment for insurrection.

The disgraced leader, who has refused to answer investigators' questions, could be jailed for life or executed if found guilty.

Yoon has meanwhile been absent from the parallel probe at the Constitutional Court, which is considering whether to uphold his impeachment.

If that court rules against him, Yoon will formally lose the presidency and elections will be called within 60 days.

F.Dubois--AMWN