SEOUL -- South Korea's anti-corruption investigative agency said on Saturday that it asked Acting President Choi Sang-mok to order the presidential security service for the execution of a warrant to arrest the impeached President Yoon Suk-yeol.

The Corruption Investigation Office for High-ranking Officials (CIO) said that it sent an official letter again to Choi, who is Minister of Economy and Finance and became an acting president after the impeachment of Yoon and the prime minister.

In the letter, the CIO asked Choi to order the security service to cooperate with the investigative agency for Yoon's arrest.

On Friday, the CIO investigators and police officers raided the presidential residence in central Seoul, but they failed to arrest Yoon after being blocked by the third and last cordon of some 200 security service agents built about 200 meters away from the residence.

It was unclear whether the acting president would cooperate as he refused to respond to the first CIO official letter that was delivered on Wednesday.

The CIO formed a joint investigation unit with the National Office of Investigation and the defense ministry's investigation headquarters to probe Yoon's martial law imposition.

The impeachment motion against Yoon was passed in the National Assembly on Dec 14 last year and was delivered to the constitutional court to deliberate on it for up to 180 days, during which Yoon's presidential power is suspended.

Yoon, who was named by investigative agencies as a suspected ringleader on insurrection charge, declared a martial law on the night of Dec 3, but it was revoked by the National Assembly hours later.