Senior aides to South Korea's impeached President Yoon Suk Yeol offered to resign en masse on Wednesday, a day after his office expressed regret over acting President Choi Sang-mok's approval of two new judges to a court set to decide Yoon's fate.

In a first for the country, a court issued an arrest warrant for a former president on charges of abuse of authority and orchestrating a rebellion.

The plane crash is the first major test for South Korea’s acting president, Choi Sang-mok, who was appointed the interim leader only on Friday, as the country grapples with a political crisis at the highest levels.

By Joyce Lee SEOUL (Reuters) -South Korea's leadership crisis will play out in the Constitutional Court, which will decide the fates of President Yoon Suk Yeol and Prime Minister Han Duck-soo, both impeached and suspended from power over a short-lived martial law.

South Korea was hit by upheaval as authorities sought an arrest warrant for the country’s impeached President Yoon Suk Yeol while investigators launched a wide-ranging inquiry into a plane crash that killed 179 people.

South Korea's acting President Choi Sang-mok said on Tuesday he would immediately move to fill vacancies on the Constitutional Court in a effort to restore stability after the impeachment of two of his predecessors this month triggered political turmoil.

A South Korean court issued an arrest warrant for embattled President Yoon Suk Yeol, who has been suspended from power over his short-lived martial law declaration, according to investigators.

A South Korean court gave authorities approval on Tuesday to detain impeached President Yoon Suk Yeol in a criminal investigation into his martial law decree, marking the first time that a sitting president of the country has faced arrest.