President Yoon Suk Yeol thanked the South Korean people for their patriotism, saying he is doing well while being held in a detention center for questioning regarding the December 3 martial law decree.

The message was delivered in a letter disclosed by his lawyer Yoon Kap-keun at around 6:15 p.m. Friday, soon after news of the anti-corruption agency's filing of his pretrial detention on charges of leading an insurrection through the decree.

The president said he has been re-reading messages he had given since taking office, including his inauguration speech and others commemorating the March First Independence Movement Day and the Liberation Day, and looking back on state affairs.

Noting that he had heard about many people showing up in a collective effort in support of the nation despite the cold weather, Yoon thanked the public for their passion and patriotic spirit.