What happens next after South Korean investigators fail to arrest impeached Yoon?

South Korean investigators with the anti-corruption investigative unit left the presidential residence after failing to arrest the impeached president Yoon Suk-yeol on Friday.

The Corruption Investigation Office for High-ranking Officials (CIO) said the continued confrontation virtually made it impossible to execute the arrest warrant, which was issued by a Seoul court on Tuesday.

It marked the first time in the country's modern history that an arrest warrant was issued against a sitting president.

Yoon, who was named by investigative agencies as a suspected ringleader on insurrection charges, declared martial law on the night of December 3. It was, however, revoked by the National Assembly hours later.

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

Tense standoff

The CIO noted that it stopped the execution at about 1:30 p.m. local time (0430 GMT) over concerns about the safety of investigators at the scene, expressing deep regret over the attitude of Yoon, who refused to comply with legal procedures.

The investigative unit added that it will decide on future measures after relevant reviews. The warrant was scheduled to be valid for a week until next Monday.

The CIO investigators and police officers attempted to arrest Yoon in the presidential residence in central Seoul, but after confronting the presidential security service agents for about five and a half hours, they had to stop proceeding with the arrest warrant.

The investigators arrived at the residence at about 7:21 a.m. local time and passed the first cordon of policemen to reach the residence's main gate some 40 minutes later.

They faced the third and last cordon of the security service inside the residence after breaking through the second cordon of soldiers.

During the process, some investigators tussled with soldiers and security agents. No injury had yet to be confirmed.

The CIO warned earlier that if the security service blocked the arrest, it would be a crime of obstruction of justice.

About 2,700 riot policemen were allegedly deployed around the residence to help proceed with the arrest warrant.

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 joint investigation unit on Friday summoned the chief of the presidential security service over the obstruction of Yoon's arrest.

An official with the investigation unit told reporters that the unit subpoenaed the chief and vice chief of the presidential security service to appear for questioning on Saturday.

The official noted that the security chief and vice chief were booked on charges of obstructing the execution of a warrant to arrest Yoon, which was issued by a Seoul court on Tuesday.

The CIO said on Friday the execution of an arrest warrant against impeached Yoon was impossible because the presidential security service refused to cooperate.

Considering the current circumstances, the CIO was calling on acting President Choi Sang-mok to order the presidential security service to cooperate with the execution of the arrest warrant, the agency said.

What happens next?

South Korea's constitutional court said Friday that it will hold hearings for Yoon's impeachment trial on January 14 and January 16.

A constitutional court justice said in the second preparatory hearing earlier in the day that the pretrial hearing had concluded, with the second one to hold a formal hearing on January 14 for the launch of formal proceedings.

The justice noted that the second formal hearing was set on January 16 in preparation for the absence of the defendant, referring to the impeached president.

Legal representatives for Yoon demanded further discussions in additional preparatory hearings, but it was dismissed by the justice.

Legal representatives for the National Assembly denounced Yoon's defense counsel for intending to delay the court proceedings.

(With input from Xinhua)