South Korea’s anti-corruption agency is seeking an extension of the arrest warrant for impeached President Yoon Suk Yeol, and for police to assist in so-far unsuccessful efforts to arrest Yoon.

The warrant approved by a court last week to arrest Yoon was set to expire Monday afternoon.

The Corruption Investigation Office for High-Ranking Officials wants to question Yoon in response to the martial law decree he issued Dec. 3, which set off a political crisis in the country and quickly led to his impeachment.

Investigators tried to execute the warrant last week, but hundreds of security forces blocked access to Yoon’s residence.

The failure prompted the anti-corruption agency to try to enlist the help of the police to execute the warrant and arrest Yoon.

Yoon’s lawyers have rejected the authority of the anti-corruption agency and called the arrest warrant unlawful.

Some information for this report was provided by from The Associated Press, Agence France-Presse and Reuters