Police in the southern Chinese province of Guangdong have arrested over 30,000 suspects as part of a crackdown on illegal gambling and pornography, Chinese state news agency Xinhua has reported.
More than 3,000 people were arrested in the province on 15 December, with 5,000 others put in criminal detention as part of the campaign.
An online gambling ring in Huizhou City involving finances of 30m yuan ($4.82m) has been busted as part of the investigation.
Gambling is illegal in China outside of Macau, except for Welfare and Sports lotteries run by the state.
Efforts are being made to suppress freedom of expression on the internet, which includes heavy scrutiny being placed on illegal gambling and pornography.