A new type of sex club in the Gangnam area is heating up debate on sexual freedom in open spaces. A theme club which opened in a Gangnam street last month is gaining popularity by allowing members to openly have sex on the premises, said police officials yesterday.

The entrance is strictly restricted to couples who have received in advance their adult age certification through the club's website.

Under the club's motto that "all sexual taboos are taboos," visitors freely have sexual relationships with their partners or involve themselves in partner swapping or group sex, according to officials. The rest of the crowd is free to watch any other couple.

The voyeuristic club is largely supported by its visitors, among whom many left messages on the website bulletin board, saying that they wished to revisit the place in the future.

Despite the social shock, however, investigators have feeble legal grounds to regulate such controversial clubs.

"The club managers claimed that many legal experts confirmed the club to be legal, as the sexual relationships are not based on prostitution but on the voluntary actions of the visitors," said a police official.

They are also planning to publish advertisements in the media this month and have finished the draft versions, according to officials.

"Considering the negative effects that it may have on the general sense of morals, we feel the need to restrict the club," said a police official.

"However, as the club is not involved in any specific illegal actions such as drug trafficking or prostitution, we have difficulties in applying any legal restrictions."

Criminal law experts also differ in their opinion concerning this unprecedented type of business.

"If all parties have a full prior understanding on the sexual activities within the club, they may only be punished for excessive physical exposure, which is only a minor offense," said Professor Cho Kuk of the Seoul National University Law School.

Cho, nevertheless, pointed out the need to add a new clause to the present criminal law that may regulate the club owner who has provided for the space for such open sexual relationships.

Though some other experts said that open sexual activities in the club hall may be legally restricted, most of them agreed that the business type narrowly escaped the control range of the present law.

The controversial club's website is presently cut off due to a traffic overload, but is under no legal restrictions, according to police officials.