South Korea's impeached President Yoon Suk Yeol has spent his first night incarcerated as a pre-trial inmate at the Seoul Detention Centre after a court issued a formal detention warrant on Sunday to hold him for up to 20 days.

South Korea's impeached President Yoon Suk Yeol had his mug shot taken and underwent a physical check before spending his first night in jail as a criminal suspect, a prison officer said Monday.

Yoon, who was impeached and suspended from office in December, is the first sitting South Korean president to be arrested.