South Korea investigators seek to extend Yoon's arrest warrant

South Korean investigators will seek an extension of a warrant to arrest impeached President Yoon Suk Yeol, an official said on Monday, as an anti-graft agency asked police to take over efforts to execute the arrest of the embattled leader.

The requests come after a failed attempt to serve the warrant on Friday following a tense stand-off with presidential security service guards who formed a human chain to block access to Yoon by the investigators.

Yoon is under criminal investigation for insurrection over his Dec. 3 martial law bid that stunned South Korea and led to the first ever arrest warrant to be issued by the court for a sitting president.

The Corruption Investigation Office for High-ranking Officials (CIO) is leading a probe, joined by police and the prosecutors' office, into allegations that Yoon masterminded insurrection with his imposition of martial law.

Yoon was impeached by parliament on Dec. 14 and suspended from presidential duties. The Constitutional Court is trying the case to decide whether to remove him from office permanently or reinstate him.

The CIO sent a notice to police requesting them to take over execution of the arrest warrant, the anti-corruption agency said in a statement to reporters. A police official told Reuters they were reviewing the request.

The move comes amid frustration among Yoon's critics towards the CIO for failing to carry out his arrest, which is due to expire at midnight on Monday (1500 GMT).

The CIO plans to request an extension of the arrest warrant in court on Monday, a CIO official said.

Yoon's lawyers have argued that the anti-graft force leading his criminal investigation has no authority under South Korean law to investigate any case involving insurrection accusations.

On Monday, Seek Dong-hyeon, a lawyer advising Yoon, said the bid to transfer the execution of the arrest warrant is effectively an admission by the CIO that its probe and the warrant were "illegal".

The Seoul Western District Court on Sunday dismissed an injunction filed by Yoon's legal team seeking to invalidate the warrants to arrest the president and search his official residence, according to Yonhap.

Amid the ongoing political upheaval, US. Secretary of State Antony Blinken is visiting South Korea this week where he is due to meet senior government officials to reaffirm the alliance with Seoul, according to the US. State Department.

His visit comes after Yoon's martial law declaration sent South Korea into political chaos, drawing rare rebuke from officials in Washington including Blinken's deputy, Kurt Campbell, who said it was "badly misjudged".

Blinken said on Monday that Washington fully trusts the resilience of South Korea's democracy and the leadership of acting President Choi Sang-mok, Seoul's finance minister.

On Sunday, Park Chong-jun, the chief of presidential security whose agents clashed with investigators trying to serve the arrest warrant on Friday, said he could not cooperate with legal action that was still being disputed.

After the failed attempt to execute the warrant, the CIO asked acting President Choi to direct the security service to cooperate with investigators. Choi has not reacted to that request, despite mounting pressure to intervene.

The CIO is an independent agency launched in January 2021 to investigate high-ranking officials including the president and their family members, but it does not have authority to prosecute a president.

Instead it is by law required to refer the case to the prosecutors' office to take any action including indictment once the questioning is over.

The unprecedented attempt to arrest an incumbent president has intensified duelling rallies by those supporting Yoon, with the "Stop the Steal" slogans popularised by US. President-elect Donald Trump voters, and those calling for Yoon's punishment.

On Monday, a group of hardcore Yoon supporters led by Christian pastor Jun Kwang-hoon held a news conference and described the fight for Yoon as an "international battle" for freedom.

"Sadly, there's no Fox News in Korea," it said in a statement, referring to the American cable news channel popular with Trump supporters.

Jun said Yoon supporters would continue rallies outside his residence until they "reap the results".