Volkswacht Bodensee - South Korea's Yoon to avoid fresh questioning after dramatic arrest

The Constitutional Court was also to hold its second hearing in a trial that will decide whether to uphold Yoon's impeachment, after the dawn raid that made him the country's first-ever sitting president to be detained.

The former star prosecutor -- facing charges of insurrection -- was questioned for hours Wednesday but exercised his right to remain silent before being moved to a detention centre.

Investigators from the Corruption Investigation Office (CIO) were to resume Yoon's questioning Thursday at 2 pm local time (0500 GMT), but his lawyer said he could not for health reasons, the Yonhap news agency reported.

"President Yoon is not well and fully explained his position yesterday so there is nothing more to be interrogated about," Yoon Kab-keun told Yonhap, an apparent reference to his Wednesday decision to not answer questions.

Lawyer Yoon confirmed to AFP the embattled leader would not attend, without specifying the reason.

CIO officials declined to comment.

Wednesday's dramatic arrest saw a hundreds-strong force of police and investigators bypass bus barricades, cut barbed wire and scale ladders to get inside the compound where Yoon was surrounded by hundreds of guards.

Yoon said Wednesday he complied with investigators to avoid "bloodshed" but did not accept the legality of the investigation.

Meanwhile, officials were trying to secure a new warrant that could hold him for longer than 48 hours.

South Korea's opposition Democratic Party celebrated Yoon's detention, while the parliament speaker said it was time to stabilise the country after weeks of turmoil.

Yoon's lawyers have instead filed for a review of the warrant that was used to arrest him.

- Trial tribulations -

Yoon shocked the nation late on December 3 when he declared martial law, claiming he needed to safeguard South Korea "from the threats posed by North Korea's communist forces and eliminate anti-state elements".

He deployed troops to parliament but lawmakers defied them and voted down the move. Yoon revoked martial law after just six hours and was later impeached by parliament.

The 64-year-old suspended leader then sought to evade arrest for weeks by remaining in his residential compound, protected by loyal members of the Presidential Security Service (PSS).

He remained defiant Wednesday after his arrest, publishing on Facebook what he said were his writings from inside the residence, repeating unproven claims of election fraud.

Shortly after he was taken to the CIO offices in a convoy, investigators began questioning Yoon but they said later he exercised "his right to remain silent".

His supporters have also refused to accept the arrest.

During the hours-long standoff between police and Yoon's guards, they chanted "illegal warrant!" while some laid on the ground outside the main gate of his residence.

In a parallel probe, the Constitutional Court is deciding whether to uphold parliament's impeachment of Yoon.

If that happens, Yoon will finally lose the presidency and fresh elections must be held within 60 days.

He was not expected to attend Thursday's hearing in person and his lawyers have requested a postponement, Yonhap reported.

The court has yet to respond to their request.

The trial can continue in Yoon's absence, even though proceedings could last for months.

T.Ziegler--VB