A police officer has been booked for investigation over his alleged involvement in the snowballing sex and corruption scandal centering on a former member of famous K-pop band BIGBANG, police said Sunday.

The officer with Gangnam Police Station, which covers Seoul's Gangnam district, where the nightclub partly ran by Seungri of BIGBANG is located, was the first incumbent police officer facing an official charge in connection with the scandal.

The officer, facing a charge of dereliction of duty, allegedly got the nightclub, Burning Sun, off the hook in an investigation into suspicions that an underage patron was allowed into the club and drank alcohol in late July last year.

He closed the case on the basis of insufficient evidence and reported the decision to the prosecution. Collusive ties are suspected between the officer and the nightclub, though police have not yet uncovered any financial transaction between the two sides.

The police plan to look into whether a former police officer, known only by his family name Kang, played any role in arranging collusion between police officers and Burning Sun.

Kang, a former officer with Gangnam Police Station, has been put in custody for allegedly brokering between Burning Sun and other police officers. A co-owner of the nightclub earlier admitted to providing 20 million won ($17,598) in bribes to Kang.

Seungri left his band last week as he faces allegations of procuring sex service for potential investors at Seoul nightclubs.

Seungri was a public relations director for Burning Sun where illegal drug use and sexual violence frequently occurred.

Another K-pop star, Jung Joon-young, is facing charges that he secretly filmed some 10 women while having sex with them and shared the files on mobile chat rooms. Having been part of the chat room, members of boy bands CNBLUE, Highlight and FT Island as well as Seungri left their bands or issued public apologies.

The scandal is likely to broaden to investigate potential collusion between Burning Sun and police officers who turned a blind eye to crimes by high-profile stars and some nightclubs in return for financial gains. (Yonhap)