The once prominent liberal politician had been out of public view since Kim Ji-eun, his secretary, revealed in a television news interview early this week that she was forced to have sex with him four times over the past eight months.

An resigned as the governor of South Chungcheong Province following the allegation.

Prosecutors launched a probe into the allegations but have yet to subpoena him. He came to the prosecution office voluntarily. 

The prosecution said they also questioned the alleged victim.

An previously announced that he would hold a press conference on Thursday to explain his stance over the situation. But he abruptly called it off two hours before the scheduled time after another allegation was made by a female research fellow at a local institute. She also claimed An sexually assaulted her.

An had been billed as a potential presidential candidate in the liberal bloc. He was the runner-up to Moon Jae-in in the Democratic Party's primary ahead of last year's presidential election. (Yonhap)