Authorities said on Monday that people who have provided protection to the sex trade in South China's Dongguan will be severely punished after a state television expose on prostitution in the city.

The Ministry of Public Security said in a statement that there will be a crackdown on organizers, operators and the "protective umbrella" of the sex trade in the city, and that local police will be investigated for dereliction of duty.

The ministry has sent a steering group to supervise an ongoing high-profile campaign against the city's rampant illegal sex trade, it added.

As of Monday morning, 12 entertainment venues involved in prostitution and other sexual services had been closed and 67 people had been investigated.

The director of a local public security bureau and the director of a police station have been suspended pending investigation, according to the Dongguan municipal public security bureau.

On Sunday, a China Central Television program revealed that a dozen hotels in Dongguan were offering sex services. In hidden-camera clips, a CCTV reporter twice called police to blow the whistle on prostitution in two hotels, but no officer showed up.