South Korea's Yoon recalled for questioning as detention deadline looms

SEOUL (Reuters) - South Korean investigators have called in arrested President Yoon Suk Yeol for questioning again, the Yonhap News Agency reported, as authorities face a Friday deadline to obtain a warrant to extend his detention or release the embattled leader.

In order to hold Yoon in custody for longer, investigators are expected on Friday to ask a court to approve a detention warrant for up to 20 days, legal experts said.

On Wednesday, Yoon became the first sitting South Korean president to be arrested over a probe into whether he committed insurrection when he briefly imposed martial law in early December. He is being held at the Seoul Detention Centre.

Although Yoon's lawyers challenged the legality of Yoon's arrest, the Seoul Central District Court struck down their challenge late on Thursday, ruling that Yoon's arrest was legal.

Yoon has been recalled for questioning at 10 a.m. (0100 GMT) on Friday, Yonhap reported, citing the Corruption Investigation Office for High-ranking Officials (CIO) which is leading the criminal inquiry. The CIO did not immediately respond to a request for comment.

It was unclear whether Yoon, who has up to now refused to answer questions put to him by investigators, would agree to attend questioning on Friday. A day earlier, Yoon refused to be questioned, with his lawyer citing his health as a factor for his absence.

Authorities have 48 hours to question the impeached president, after which they must release him or seek a warrant to detain him for up to 20 days.

The 48-hour countdown is expected to end on Friday evening after it was paused to allow a court to review the challenge to his arrest, Yonhap said, citing the CIO.

Yoon's lawyer Seok Dong-hyeon said on Friday investigators were expected to seek a detention warrant, adding "we hope that there will be more careful and comprehensive consideration" of the arrest's "illegality" when a court reviews the warrant.

South Korea is grappling with its worst political crisis in decades, sparked by Yoon's brief attempt to impose martial law on Dec. 3 that was voted down by parliament.

Neighbouring North Korea has largely avoided public comment on the political chaos in Seoul, but Yoon's arrest was reported in state media on Friday, two days after the event.

The Rodong Sinmun newspaper cited foreign media to say it was the first arrest of an incumbent president in South Korea.

"Yoon Suk Yeol is not following legal procedures at the expense of the national order for individual interests," Rodong Sinmun said.

(Reporting by Joyce Lee; Editing by Ed Davies and Sonali Paul)