SEOUL (Reuters) -South Korean investigators again asked the country's acting president on Saturday to order the presidential security service to comply with an arrest warrant for impeached President Yoon Suk Yeol.

The impeachment of South Korea’s acting President Han Duck-soo has plunged the country into further political turmoil, coming less than two weeks after lawmakers impeached President Yoon Suk Yeol.

The vote was the second major impeachment in two weeks after President Yoon’s ill-fated martial law bid set off turmoil. The country’s currency has plunged.

The impeachment of Han Duck-soo, acting president since Yoon was impeached on Dec. 14 for declaring martial law, has thrown South Korea's once-vibrant democratic success story into uncharted territory.

South Korean lawmakers voted on Friday to impeach acting president Han Duck Soo, barely two weeks after Yoon Suk Yeol was removed from the presidency over his imposition of martial law. A total of 192 lawmakers in the opposition-controlled parliament voted to impeach Han - significantly more than the simple majority required.

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.

South Korea's main opposition party vowed on Tuesday to impeach acting president Han Duck-soo but reversed an earlier plan and decided to wait until later in the week, party officials said, as the risk of further political uncertainty heightened.

Thousands braved heavy snow in Seoul on Sunday to rally for and against arresting impeached President Yoon Suk Yeol, as South Korea's political crisis appeared headed toward another high-stakes confrontation.