Opposition parties doubled down on their calls for an independent counsel to look into financial fraud scandals that cost investors several trillion won, after hearing testimony alleging corrupt ties between the financial companies and the government and ruling party.

Joo Ho-young, floor leader of the main opposition People Power Party, said Monday that the party would submit a bill proposing a special probe by an independent counsel.

“The ruling and the opposition parties should halt political strife surrounding the matter and entrust the case to special prosecutors for a thorough investigation. We will submit the bill as soon as possible,” Joo said.

The quarrel intensified between rival parties over the prosecutors’ ongoing investigation into two corruption scandals. One involved hedge fund Lime Asset Management, once the country’s largest, and the other involved Optimus Asset Management. The funds respectively suspended the redemption of funds worth some 1.6 trillion won ($1.47 billion) and 500 billion won.

The scandals deepened after people who played key roles testified that they had lobbied prosecutors, presidential officials and lawmakers of the ruling and opposition parties to conceal wrongdoing.

Lawmakers who attended the parliamentary annual inspection of state affairs on Monday, lashed out at each other by unveiling the names of politicians who were embroiled in the cases.

Interior Minister Chin Young and Rep. Kim Kyung-hyup were among lawmakers of the ruling Democratic Party and Cheong Wa Dae officials who made investment for Optimus funds, according to Rep. Yoo Sang-beom of the People Power Party.

The ruling party fired back at those who were mentioned by Kim Bong-hyun, former chairman of Star Mobility, who is believed to be the main financial backer of Lime Asset in his letter disclosed on Oct. 16.

In the letter, he said he gave several hundred million won to a senior prosecutor-turned-opposition politician and spent 10 million won in July last year to throw a drinking party for three incumbent prosecutors, and that one of those prosecutors had taken part in the investigation into the Lime scandal.

He also alleged the prosecution encouraged him to cooperate in their investigation that targets heavyweight politicians of the ruling party.

Following the revelation of the letter, the Justice Ministry criticized the Prosecutors’ Office for failing to conduct a thorough investigation to determine whether prosecutors or opposition party lawmakers had anything to do with the case.

The Supreme Prosecutors’ Office rebutted the accusation, calling the ministry’s statement “slander.”

Kim Chong-in, interim leader of the People Power Party, urged the ruling Democratic Party of Korea to accept his party’s proposal and reopen the case with an independent counsel.

“No one would trust the objectivity of the ongoing investigation when the prosecution office and the Justice Ministry fight against each other,” he said.

The ruling Democratic Party opposed the launch of the independent counsel as it could take months to deal with procedures for the passage of the bill and formation of its investigation team.

“A special probe will not be efficient. The Democratic Party’s stance is that the ongoing prosecution investigation should be carried out promptly and efficiently,” the party’s spokeswoman Hong Jung-min said.

By Park Han-na (hnpark@heraldcorp.com)