A major police crackdown is targeting China’s prostitution capital, in the city of Dongguan, located in southern China’s Guangdong province. Over the weekend, more than 300 establishments in what is known as China’s Sin City were raided by police, leading to the arrests of 67 people.

Prostitution is rampant in Dongguan, but often masked by businesses operating as karaoke clubs, saunas, massage parlors, and even a few luxury hotels. According to state-run Xinhua News Agency, China’s sex capital has been labeled “under siege” as the government plans to clamp down on the sex industry. On Sunday, Hu Chunhua, Guangdong’s party chief, called for a “thorough investigation and crackdown,” enlisting more than 6,500 police officers in the area as part of a greater effort to do away with sleaze.  

The crackdown was prompted by a CCTV news exposé, which showed an undercover journalist looking into so-called “beauty pageants” that feature prostitutes and strippers, held for customers at the aforementioned venues, comparable to ordering them off a menu. “You just lie down there and the lady will serve you all around,” one female manager said in the hidden-camera video. The CCTV report accused the city’s lax leadership of allowing the city to “fall into decay,” and for permitting such an industry to flourish and become what it is today. According to a report by the Telegraph, between 500,000 and 800,000 people have been employed directly or indirectly by Dongguan’s robust sex trade in 2009.

In response to a firestorm of media coverage, Guangdong’s public security ministry vowed to take down the industry with “an iron fist” and investigate claims that officials have been turning a blind eye to local gangs and pimps.

The CCTV story elicited a strong and rapid response from officials, with the first of a series of raids in the area just hours after the report aired. The first target was a hotel, the Ding’an Holiday Hotel, with the detention of 10 suspects, including the hotel’s manager. By Monday morning, less than a day after the report, dozens of arrests were made, in addition to two senior police chiefs being suspended.

Prostitution became illegal after the Communist Party took power in 1949 but has been as an open secret, thriving in boomtowns or factory cities like Dongguan, Shenzhen, and Foshan, all of which have developed a reputation for an underground sex scene.