Hours after South Koreas impeached President Yoon Suk Yeol was formally arrested, triggering rioting by his supporters, his lawyers said Sunday that he remains defiant in his refusal to answer questions over the probe into his declaration of martial law last month.RELATED STORY | South Korea's impeached President Yoon detained in major law enforcement operationYoon was formally arrested early on Sunday, days after being apprehended at his presidential compound in Seoul. He faces possible imprisonment over his short-lived imposition of martial law, which set off the countrys most serious political crisis since its democratization in the late 1980s.Yoons arrest could mark the beginning of an extended period in custody, lasting months or more.The decision to arrest Yoon ignited unrest at the Seoul Western District Court, where dozens of his supporters broke in and rioted, destroying the main door and windows. They used plastic chairs, metal beams and police shields that they managed to wrestle away from officers. Some were seen throwing objects and using fire extinguishers, destroying furniture and office machines, smashing glass doors and spraying water on computer servers. They shouted demands to see the judge who had issued the warrant, but she had already left.RELATED STORY | South Korean lawmakers impeach nation's president for a second time in DecemberHundreds of police officers were deployed and nearly 90 protesters were arrested. Some injured police officers were seen being treated at ambulance vans. The court said it was trying to confirm whether any staff members were injured and assess the damage to its facilities.In a statement issued through lawyers, Yoon lamented that the court did not recognize the just purpose of his martial law decree but also urged his supporters to express their frustrations peacefully. He called on the police to adopt a lenient stance toward the protesters.But hundreds of Yoons supporters continued to clash with police as they extended their rallies into the evening in front of Seouls Constitutional Court, which is holding separate deliberations on whether to formally remove the impeached president from office or reinstate him. At least three protesters were detained at the scene. There were no immediate reports of damage to the court, which was barricaded by police.