A policeman samples a girl's saliva for her DNA record.
(Yangcheng Evening News)

Police in the southern Chinese city of Guangzhou have begun demanding DNA samples from workers at nightclubs and karaoke bars, in a move that is stirring controversy, a report said.

Baiyun district police are recording the DNA, fingerprints and handwriting of employees in entertainment venues as a requirement for receiving a certificate to continue work, the Yangcheng Evening News said Thursday.

One police station has already taken records of 4,233 employees from 118 venues.

Station deputy director Long Shijun said the DNA database helped to track down criminals.

"Such a supervision mechanism can not only keep information for crimes that may happen in the future, but also it can check the ID of people who are employed by the industry," he was quoted as saying.

Long said karaoke bars and other entertainment venues had mushroomed in the district since 2005 and needed stronger supervision to eliminate their crime potential.

He maintained that the DNA record-taking and fingerprinting did not violate personal privacy.

"Records of that information will be sent directly to the city police's database. Records won't be leaked," he said.

But reports of the police requirement have stirred controversy among local citizens, who are divided over whether it is a good move in the fight against crime or a violation of personal privacy, the Yangcheng Evening News and other Guangzhou papers said.

The city already has China's biggest DNA database, with about 300,000 records. It also has more than three million sets of fingerprints.