South Korean prosecutors charged President Yoon Suk Yeol for his failed attempt last month to place the country under martial law, Yonhap News Agency said, forcing the impeached leader to remain in detention as they build a case against him.

Impeached South Korean President Yoon Seok Yeol was indicted for his martial law declaration that plunged the country into political turmoil, with prosecutors accusing him of being a "ringleader of insurrection".

South Korea's impeached President Yoon Suk Yeol has been charged with insurrection after he attempted to declare martial law in December. His ill-fated attempt to impose military rule plunged the country into an unprecedented political crisis and he becomes the first sitting president in South Korean history to be charged with a crime.