The ruling Saenuri Party on Friday vowed to get to the bottom of allegations that one of its lawmakers bribed her way into parliament as it scrambled to contain the fallout ahead of December's presidential election.

The scandal centers on suspicions that Rep. Hyun Young-hee secured a proportional representative seat in April's general elections after paying 300 million won ($265,960) to Hyun Ki-hwan, then a member of the party's candidate nomination committee.

Saenuri launched an official internal probe on Thursday made up of nine members, including five lawyers. There have been calls for the resignation of party Chairman Hwang Woo-yea over the scandal and demands that the party's leading presidential hopeful Rep. Park Geun-hye formally apologize. The former chairwoman of the conservative party has seen her approval ratings dip because of the scandal.

Lee Bong-hee, a lawyer chairing the committee who previously served as chief of the Seongnam branch of the Suwon District Prosecutors' Office, said every effort will be made to find the truth so it can alleviate all public suspicions surrounding the case whose details remain murky.

"It is impossible to predict how the probe will progress, but it will be conducted in an independent manner," he said. The attorney added that telling the public the entire truth is critical so the party can move forward with its plans to pick a presidential candidate on Aug. 20 and win the Dec. 19 race to pick the country's next chief executive.

The in-house investigation comes as state prosecutors are conducting their own investigation into the case that involves a sitting lawmaker, a former parliamentarian and former party officials.

(Yonhap News)