IDG News Service — China has paid cash rewards to more than 200 people who found online porn and reported it to authorities, as a government crackdown on undesirable Web content spreads.

Authorities gave the people a total of 224,000 yuan (US$33,000) as part of a policy to pay citizens for porn tip-offs, the official Xinhua news agency said late Monday. The policy caused a government watchdog's daily number of porn tip-offs from the public to surge by 10 times immediately after it was announced last month, according to Xinhua.

The news comes as China continues a crackdown on so-called "harmful" online content that has spread from conventional porn Web sites to mobile porn and to online games. Starting soon, residents of Beijing and Shanghai who send text messages containing "illegal or unhealthy" content over the network of China Mobile, the world's largest mobile carrier by subscribers, will be temporarily blocked from sending more text messages, the official China Daily newspaper said.

China blocked or shut down more than 15,000 pornographic Web sites last year, Xinhua said.

Online games also came further under the eye of Chinese authorities this week as the country's culture ministry announced the formation of a "self-discipline" industry association including game developers and operators as members. The Chinese government has often used such arrangements to encourage self-censorship, whether of pornography or of sensitive political content, by operators of Internet services such as blogs. Regulators previously called for online games to cut back on systems that let players get married or earn experience points by killing monsters.

Regulators this year plan to launch a rating system for online games to protect young players from vulgar content, the China Daily said.