, in a message to conservative supporters rallying outside his Seoul residence, vowed to 鈥渇ight to the end鈥� against 鈥渁nti-state forces,鈥� while his legal team warned Thursday that police officers could face arrest by his presidential security service or even civilians.

Yoon鈥檚 latest statement of defiance came as the Corruption Investigation Office for High-Ranking Officials prepared to execute a detainment warrant against him that was issued by a Seoul court on Tuesday and is valid for one week. The warrant was issued after Yoon evaded and blocked searches of his office, hindering an investigation into whether his hourslong martial law imposition on Dec. 3 amounted to rebellion.

Oh Dong-woon, the anti-corruption agency鈥檚 chief prosecutor, has indicated that police forces might be deployed if Yoon鈥檚 security service resists the detention attempt, which could occur as early as Thursday. But it remains unclear whether Yoon can be compelled to submit to questioning.

Yoon鈥檚 legal team issued a statement on Thursday warning that any attempt by the anti-corruption agency to use police units for his detention would exceed their legal authority. The lawyers said police officers could face arrest by either the 鈥減residential security service or any citizens鈥� if they try to detain Yoon. They didn鈥檛 elaborate further on the claim.

South Korean law permits anyone to make an arrest to stop an active crime, and critics accused Yoon of inciting his supporters to obstruct attempts to detain him.

In a message to supporters gathered outside his residence Wednesday evening, Yoon said he would continue to fight against anti-state forces 鈥渧iolating our sovereignty鈥� and putting the nation in 鈥渄anger.鈥� He applauded his supporters for their efforts to protect 鈥渓iberal democracy and constitutional order鈥� and said he was watching their protests on live YouTube broadcasts, according to a photo of the message shared by Yoon鈥檚 lawyers.

Yoon Kap-keun, the president鈥檚 lawyer, filed a challenge with the Seoul Western District Court on Thursday to block both the detention warrant for Yoon Suk Yeol and a related search warrant for his residence. The lawyer argued that both warrants violate criminal laws and the constitution.

The liberal opposition Democratic Party, which drove the over his imposition of martial law, accused the president of trying to mobilize his supporters to block his detention and called for law enforcement authorities to execute the warrant immediately.

Braving subfreezing temperatures, thousands of Yoon鈥檚 supporters rallied for hours near his residence on Thursday amid a heavy police presence, waving South Korean and American flags while chanting, 鈥淣ullify the impeachment!鈥� and 鈥淲e will protect President Yoon Suk Yeol!鈥� Officers removed some protesters who laid down on a road leading to the entrance of Yoon鈥檚 residence, but there were no immediate reports of major clashes.

鈥淭he Corruption Investigation Office must detain him immediately, and the presidential security service must cooperate with the lawful execution of the detainment warrant,鈥� said Park Chan-dae, the Democrats鈥� floor leader.

鈥淭hey should be aware that obstructing the execution of the detainment warrant could result in punishment for interference with official duties and complicity in rebellion,鈥� he said.

Yoon鈥檚 lawyers have argued that the court鈥檚 detainment warrant is invalid, claiming that the anti-corruption agency lacks the legal authority to investigate rebellion charges. They also accuse the court of bypassing a law that says locations potentially linked to military secrets cannot be seized or searched without the consent of the person in charge.

Some experts believe the anti-corruption agency, which is leading a joint investigation with police and military authorities, would not risk clashing with Yoon鈥檚 security service, which has said it will provide security to Yoon in accordance with the law. The office may instead issue another summons for Yoon to appear for questioning if they are not able to execute the detainment warrant by Jan. 6.

If Yoon is detained, the anti-corruption agency will have 48 hours to investigate him and either request a warrant for his formal arrest or release him. Yoon鈥檚 defense minister, police chief and several top military commanders have already been arrested over their roles in the martial law enactment.

Yoon鈥檚 presidential powers were suspended following a National Assembly vote to impeach him on Dec. 14 over his imposition of martial law, which lasted only hours but has triggered weeks of political turmoil, halted high-level diplomacy and rattled financial markets. Yoon鈥檚 fate now lies with the Constitutional Court, which has begun deliberations on whether to uphold the impeachment and formally remove Yoon from office or reinstate him.

To formally end Yoon鈥檚 presidency, at least six justices on the nine-member Constitutional Court must vote in favor.

The National Assembly voted last week to also impeach Prime Minister Han Duck-soo, who became acting president after Yoon鈥檚 powers were suspended, over his reluctance to fill three Constitutional Court vacancies ahead of the court鈥檚 review of Yoon鈥檚 case.

Facing growing pressure, the new acting president, Deputy Prime Minister Choi Sang-mok, appointed two new justices on Tuesday, which possibly increased the chances of the court upholding Yoon鈥檚 impeachment.

Cho Han-chang, one of the newly appointed justices, said Thursday that he began his job with a 鈥渉eavy heart.鈥� Jeong Gye-seon, the other new justice, expressed hope that the remaining vacancy would be filled.

Yoon鈥檚 imposition of martial law ended after only six hours when the National Assembly voted 190-0 to lift it despite attempts by heavily armed soldiers to prevent them from voting.

Yoon has defended his martial law decree as a necessary act of governance, portraying it as a temporary warning against the Democratic Party, which he has described as an 鈥渁nti-state鈥� force obstructing his agenda with its legislative majority.

Kim Tong-hyung, The Associated Press