South Korea's first swingers' club -- where couples can swap partners for sex -- has made a roaring debut, leaving police who want to close it down struggling to respond.

The club opened earlier this month in Seoul's prosperous Kangnam District where business appears to be thriving, with many visitors writing favourable comments on its website about their experience.

"Say no to sex-related taboos," it proclaims on its homepage.

The club only accepts adults who have booked online. Couples watch or have sex with one or more partners.

"Law experts told us there is no legal basis to crack down on this club," where consenting adults have sex in a closed space, one of its unidentified owners was quoted as telling the Yonhap news agency.

Police admitted that it would be difficult to apply existing laws banning prostitution or obscene performances in this case.

Still, "we've told the Kangnam police station to find legal provisions to crack down on it," said Yang Sung-Cheol, a senior officer at the Seoul Police Agency.

After news reports about the club, its website crashed under the strain of thousands of people trying to log on at the same time.

http://news.yahoo.com/s/afp/20090630/wl_asia_afp/lifestyleskoreasex_20090630151735