In Guangzhou, clients wanting to stay overnight in sauna and massage¹ parlors³ must now show ID and register their personal information, according to the city's security bureau's latest regulations.

"The regulation went into effect at 1 am yesterday," says He Jing, deputy director of the security bureau of Guangzhou, capital of Guangdong province.

"It affects people going to sauna and massage venues⁴ from 1 am to 8 am only, visitors to these venues at other times will not be affected⁵" he said.

The point of the stipulation⁶ is to prevent criminal suspects from hiding out in such establishments, as well as inhibit⁷ the sex trade, He said.

"Some of these health centers have become dens⁸ of iniquity⁹ in past years owing to an absence of efficient supervision¹⁰ and management," He said, adding "Sauna and massage venues are entitled to refuse admission to clients who refuse to register their ID ".

The security bureau will regularly dispatch investigators¹¹ to ensure the new regulation is upheld.

Penalties imposed on those found to be in violation¹² of the regulation range from warnings to revocation¹³ of business licenses¹⁴.

Sauna and massage parlor² proprietors¹⁵ say the new regulation affects business and regular clients as it infringes¹⁷ on their privacy.

Chen Zhaomin, a Guangzhou resident who has hitherto been a regular overnight patron of sauna and massage venues, went home early yesterday morning rather than register his ID at a sauna house in the city's Tianhe district.

"I chose to leave because I think registering under my real name is an imposition," the 33-year-old told the China Daily.

A sauna proprietor¹⁶ surnamed Dong said the regulation has negatively affected his business.

"On average, 100 clients stay overnight at our sauna center every day throughout the year. During peak periods, such as the biannual¹⁸ trade fair, as many as 300 clients stay overnight " Dong said.

"But last night when the regulation came in to force, only 60 people stayed."

Ms Li Hongwei, a white- collar worker, said she thought the regulation would improve the management of the city's entertainment venues and crack down on the sex trade.

"Many entertainment venues in Guangzhou have recently become hotbeds of vice," she told China Daily.

Lin Lingfeng, a local lawyer, said the regulation standardizes¹⁹ operation of the city's entertainment venues.

"It has the same legal basis as showing proof of identity when checking into a hotel, opening a bank account or applying for a phone line," Lin said.