Officials from a joint investigation team looking into President Yoon Suk Yeol's short-lived martial law declaration arrive at the presidential office in Seoul to deliver notices for questioning, Monday. Yonhap

President Yoon Suk Yeol continues to defy summons issued by investigative authorities for questioning over his botched martial law, raising the possibility that he may face forced detention, according to legal and political experts.

A joint investigation team comprised of the police, the Corruption Investigation Office for High-ranking Officials (CIO) and the defense ministry, attempted to deliver a written summons to Yoon at the presidential office and his residence in central Seoul, Monday.

They were seeking to question Yoon at 10 a.m. on Wednesday at the CIO's office in Gwacheon, Gyeonggi Province, on charges of treason and abuse of power as the head of the insurrection.

However, officials at both locations refused to accept the document. The Presidential Security Service said it is not responsible for handling the summons, while the presidential secretaries' office also claimed it would be inappropriate for them to pass the document to the president, whose duties have been suspended.

Despite the failed in-person attempts, the team said the summons had already been sent by mail earlier in the morning, ensuring its delivery through alternate means.

However, it has not been disclosed whether the president's side received the mail.

When asked if investigators are considering forcibly detaining the president if he continues to refuse the summons, one member said that option is not being considered at the moment.

Separately from the joint team, the prosecution, which is conducting its own investigation into the same case, also requested on Monday that Yoon appear before the Seoul Central District Prosecutors' Office for questioning.

It was the prosecution's second summons, as it previously notified Yoon, Wednesday, to appear for questioning at 10 a.m. on Sunday. But he did not show up, with Yoon's side saying the president has yet to put together his legal team.

Former Korea Communications Commission Chief Kim Hong-il is expected to lead the president's defense team, according to Yoon's legal counsel.

If he complies with the request, Yoon would be the first sitting president of Korea to be summoned for questioning. Previously, four former presidents faced summons, but only after their terms in office had ended.

But experts believe Yoon is highly likely to continue refusing to comply, given his public statements and his current position on the matter. If the president persists in defying the summons without valid justification, the chance of detention may increase.

According to legal experts, it is customary to issue an arrest warrant to forcibly summon a suspect who ignores three requests to appear before investigators.

People watch President Yoon Suk Yeol's televised address at Seoul Station, Thursday, explaining the reasons behind his declaration of martial law on Dec. 3. Yonhap

"Considering the president's actions and public statements, it is evident that he believes his declaration of martial law was justified," said Choi Chang-ryul, a political science professor at Yong In University.

"The presidential residence and office are off-limits areas and executing a warrant in those places requires the approval of the person in charge," he said. "Since that person is the president himself, securing his custody will not be an easy task."

Political commentator Rhee Jong-hoon also emphasized the likelihood of Yoon continuing to defy the summons, despite the procedural inevitability of arrest if he refuses to comply.

"Yoon may continue to refuse, citing the need to assemble a defense team and prepare a strategy for his statement," he said.

He added that predicting Yoon's next move is difficult, describing the president's actions so far as "unpredictable."

Meanwhile, the investigave authorities' decision to publicly announce the summons appears to be fueled by testimonies from three high-ranking military commanders, who identified Yoon as the central figure in the alleged treason plot.

The three commanders — Lt. Gen. Yeo In-hyung, former chief of the Defense Counterintelligence Command, Lt. Gen. Kwak Jong-keun, head of the Army Special Warfare Command, and Lt. Gen. Lee Jin-woo, head of the Capital Defense Command — reportedly provided detailed accounts of Yoon's involvement.

Their statements provide detailed accounts of discussions about the potential imposition of emergency measures prior to its declaration, along with allegations that the president issued orders on the day the measures were enacted.

Investigations into those involved in the martial law declaration are gaining momentum, with an arrest warrant issued on Monday for Kwak over his suspected role in the incident. Kwak becomes the second military official facing arrest, following Yeo, who was detained on Saturday.