Police said Friday they are considering widening their investigation into other high-ranking officials possibly implicated in a burgeoning sex-for-favors scandal that rocked the nation and forced a vice justice minister to resign.

“We can investigate other figures if they are considered relevant to the crime. … We secured testimonies of two or three women who claim to be victims,” a police official was quoted as telling Yonhap News.

On Thursday, Vice Justice Minister Kim Hak-ui resigned amid his alleged involvement in the scandal where a number of high-ranking officials allegedly received sexual services from a contractor identified by his surname Yoon in exchange for exerting their influence.

The case showed signs of escalating into a full-fledged scandal as news reports raised fresh allegations that an official from the National Intelligence Service could also be involved.

Police believe at least 10 people from government, the judiciary, medical and media industries were among guests Yoon invited to his holiday home in Gangwon Province for sex parties.

The allegations were first brought to surface by a businesswoman surnamed Kwon, who once had personal relations with Yoon, in the process of a legal battle between the two.

Kwon had testified that Yoon hired women to provide sexual services for influential figures from a wide range of fields at his luxury country home in Wonju between 2008 and 2012, and that he filmed the scenes and kept the video footage as blackmail.

Rumors have since snowballed with claims that Kim Hak-ui was one of the officials in the videos.

Kim is suspected of having visited Yoon’s holiday home in 2009 while he was serving as head of the regional prosecutors’ office.

Police have reportedly obtained statements from Kwon and other women who identified the man in the video as Kim.

Kim has been denying the allegations saying that he will take legal action against the news reports.

The police are currently inspecting a two-minute-long sex video clip believed to have been used for bribery by Yoon, and are now seeking a search warrant for his country house in Wonju to secure further evidence.

They also imposed a travel ban on Yoon and summoned his nephew, who is thought to have collaborated with Yoon.

Observers say if the allegations turn out to be true, the sexual bribery scandal would be an unprecedented case in the country involving a number of high-rank social leaders.

But it so far remains unclear whether and how the involved parties will be prosecuted. It is generally considered difficult for suspects to face criminal charges for simply appearing in a video as it is difficult to prove the connection between the sexual services and compensation. To be prosecuted, clear evidence of lobbying and exchanging money in return for sex are required.

By Oh Kyu-wook (596story@heraldcorp.com)