A Ministry of Justice van, presumed to be carrying impeached President Yoon Suk Yeol, departs to attend a hearing on his formal arrest over a botched attempt to impose martial law, held in the Seoul Western District Court, Seoul, Jan. 18. Yonhap

The state anti-corruption agency said Monday it is "strongly" considering bringing President Yoon Suk Yeol in by force as he repeatedly defies its orders to appear for further questioning over his failed martial law bid.

Yoon, who has been held at the Seoul Detention Center since last Wednesday and was placed under formal arrest Sunday, snubbed an order by the Corruption Investigation Office for High-ranking Officials (CIO) to appear for questioning at 10 a.m., the second day in a row he has done so.

"At this stage, I can say we are strongly considering bringing him in by force," a CIO official told reporters. "We have not ruled out a visit to the detention center for questioning and are considering that as well."

Yoon will be held in custody until Jan. 28, and if a court grants an extension, until Feb. 7, the official said.

The CIO will continue talks with the prosecution over when to transfer the case to them for further investigation and potential indictment.

The impeached president faces charges of leading an insurrection and abusing his power through his short-lived imposition of martial law on Dec. 3.

He was formally arrested early Sunday after a court issued a warrant to extend his detention over concerns he might destroy evidence.

Large numbers of Yoon's supporters stormed the court after the warrant's issuance in protest, injuring police officers and damaging the building.

The CIO official said the agency will seek the cooperation of the police to ensure the safety of investigators probing the case. (Yonhap)