Former South Korean president Yoon Suk Yeol was detained for a second time on Thursday and placed in solitary confinement as investigations continue into allegations of insurrection.Yoon is accused of attempting to subvert civilian rule by declaring martial law on December 3 and deploying armed soldiers to parliament to prevent lawmakers from rejecting the declaration. The incident triggered a major political crisis in South Korea.He was first arrested in January after resisting detention for weeks, using his presidential security team to block investigators. That arrest made him the first sitting president in South Korean history to be taken into custody. He was later released in March on procedural grounds, though his trial on insurrection charges remained ongoing.Following his impeachment in April, confirmed by the Constitutional Court, Yoon refused to comply with multiple summons from investigators. Authorities then sought a second detention, citing concerns he would destroy evidence.A judge at the Seoul Central District Court approved the latest arrest early Thursday. Yoon, 64, was then moved to a detention center near Seoul, where he will remain in solitary confinement for up to 20 days while prosecutors prepare formal charges. If indicted, he could be held for up to six additional months.“Once Yoon is indicted, he could remain detained for up to six months following indictment,” said Yun Bok-nam, president of Lawyers for a Democratic Society, while talking to AFP. “Theoretically, immediate release is possible, but in this case, the special counsel has argued that the risk of evidence destruction remains high, and that the charges are already substantially supported,” he added.On Wednesday, Yoon attended a seven-hour hearing where he denied all charges. He told the court he was “fighting alone” and that his legal team was under pressure, with lawyers withdrawing one by one.“One by one my lawyers are stepping away, and I may soon have to fight this alone,” said Yoon as quoted by AFP.Yoon’s lawyers argued the detention was unnecessary, noting he no longer holds any official power. However, prosecutors pointed to the risk of evidence destruction and the seriousness of the charges.Investigators recently questioned Yoon about his resistance during the failed arrest in January and allegations that he authorised drone flights to Pyongyang to justify martial law. He also faces charges of falsifying official documents tied to the martial law attempt.The former President has defended his actions, saying martial law was necessary to eliminate pro–North Korean and anti-state elements. But the Constitutional Court called his actions a “betrayal of people’s trust” and a “denial of the principles of democracy.”Current President Lee Jae Myung, elected in June, has approved special investigations into Yoon’s declaration of martial law and other criminal allegations involving his administration and wife.