What lies ahead for South Korea's impeached president as investigators seek his arrest?

SEOUL, South Korea — Law enforcement authorities on Friday requested a court warrant to formally arrest South Korea's impeached president, Yoon Suk Yeol, who was in his third day at a detention center after his lawyers failed in a last-minute effort to secure his release.

Yoon, who was apprehended on Wednesday in a massive law enforcement operation at his residence, faces potential rebellion charges linked to his declaration of martial law on Dec. 3, which set off the country's most serious political crisis since its democratization in the late 1980s.

Yoon's detention, authorized by a court warrant compelling him to face investigation after repeatedly ignoring summonses from law enforcement, was valid until 9:05 p.m Friday. But he will remain in custody as a Seoul court deliberates whether to put him under formal arrest.

If Yoon is arrested, investigators can extend his detention to 20 days, during which they will transfer the case to public prosecutors for indictment.

Attempting to break through legislative gridlock, Yoon imposed military rule and sent troops to the National Assembly and election offices, but the standoff lasted only hours after lawmakers who managed to get through a blockade voted to lift the measure. The opposition-dominated assembly voted to impeach him on Dec. 14.

A court-ordered arrest could lead to an extended period in custody for the conservative president, who faces both criminal charges and a Constitutional Court ruling in the coming weeks that will determine whether he is dismissed or reinstated to office.

Here's what Yoon faces at a moment that could determine his political fate:

On Friday afternoon, the Corruption Investigation Office for High-Ranking Officials, which is leading a joint investigation with police and the military, requested the Seoul Western District Court to grant a warrant for Yoon's formal arrest.

The court will hold a hearing Saturday afternoon, which Yoon may or may not attend, before it decides whether to grant his arrest. That could come sometime over the weekend or early Monday.

Details of the arrest warrant request wasn't immediately available. In issuing a warrant for Yoon's detention this month, the court stated that he was facing potential charges of leading a rebellion.

After undergoing more than 10 hours of questioning on Wednesday at the anti-corruption agency's headquarters in Gwacheon, during which he exercised his right to remain silent, Yoon boycotted questioning for a second straight day on Friday as his supporters maintained that the investigation was illegal.

In a message to his supporters, conveyed through lawyers, Yoon said he was doing well in detention and thanked them for coming out to the streets in cold weather to show their ''fervent patriotism.'' Hundreds of Yoon supporters gathered near the Seoul Western District Court, shouting slogans calling for his release.

Yoon's defense minister, police chief, and several top military commanders have already been arrested for their roles in the enforcement of martial law.

What happens if Yoon is arrested?

If Yoon is formally arrested, that could mark the beginning of an extended period in custody for him, lasting months or possibly longer.

If prosecutors indict Yoon on rebellion and abuse of power charges, which are the allegations being examined by investigators, they can possibly keep Yoon under arrest for up to six months until an initial court ruling. If the first court convicts him and issues a prison term, Yoon would serve that sentence as the case possibly moves up to the Seoul High Court and Supreme Court. Under South Korean law, orchestrating a rebellion is punishable by up to life imprisonment or the death penalty.

Yoon's lawyers have argued that there is no need to detain him during the investigation, saying he doesn't pose a threat to flee or destroy evidence.

Yoon has steadfastly denied accusations that his martial law decree was an attempt at rebellion, contradicting the testimonies of military commanders who have described an attempt to shut down the legislature. Critics say this makes him a potential threat to destroy or tamper with evidence.

What key points will be contested in court?

To avoid conviction on rebellion charges, Yoon would need to support his claim that martial law was intended as a temporary and ''peaceful'' warning to the liberal opposition, which he accuses of obstructing his agenda and paralyzing state affairs with its legislative majority.

Yoon and his lawyers have claimed that he had no intention of stopping the functioning of the National Assembly, stating that the deployment of troops was intended to maintain order, not prevent lawmakers from entering and voting to lift martial law. They have claimed that the troops sent to the assembly were unarmed and denied allegations that Yoon ordered the arrest of key politicians, including National Assembly Speaker Woo Won Shik and opposition leader Lee Jae-myung.

Military commanders, however, have described a deliberate attempt to seize the legislature that was thwarted by hundreds of civilians and legislative staff who helped lawmakers enter the assembly, and by the troops' reluctance or refusal to follow Yoon's orders.