The prosecution accused Han of abetting former President Yoon Suk Yeol in declaring martial law and committing perjury, Park Ji-young, the spokesman, told reporters.

Yoon is already facing a criminal trial on insurrection charges. In April, the conservative leader was removed from office over his botched bid to impose martial law, which plunged the country into political turmoil.

Han, who was prime minister under Yoon, became acting president after Yoon was impeached. He then resigned from the post to run in a June election to become the next president but ended his bid following rifts among conservatives.

Reuters could not immediately reach Han for comment.

In recent weeks, prosecutors have been questioning Han in relation to the martial law case, but Han has not responded to questions from reporters.