South Korean President Moon Jae-in called for an investigation into a sex and corruption scandal involving Seoul's nightclubs after a K-Pop star underwent questioning last week about alleged links to prostitution.

Moon said the case includes "strong allegations of consent, backing and favors" for clubs by police and tax officials, adding it would be a "huge shock" if they were true, according to a statement from his office released Monday.

The scandal has marred the reputation of the K-Pop industry, one of the country's most prominent exports along with Samsung phones. Seungri, a member of the five-man Big Bang boy band, was questioned by police after local broadcaster SBS reported he may have provided guests with prostitutes at a club in the Gangnam district. MBC reported separately last month drugs might have been used at another club where Seungri was an executive.

Seungri has denied wrongdoing and has not been charged. The scandal grew when SBS reported this month separately that another K-Pop celebrity, Jung Joon-young, sent Seungri and other entertainers a chat message with a spy-cam video showing him having sex with a woman. Jung, who is also being investigated, has apologized and admitted the allegations, according to South Korea's Yonhap news agency.