The Ministry of Public Security has released new software designed to keep cults, sex and violence off the Internet in China, a police official said.
The software, Internet Police 110, is named after the police emergency number.
It will prevent users from getting "unhealthy" information from foreign and domestic websites, he told Reuters.
The software - which comes in three versions for households, Internet cafes and schools - can also monitor Web traffic and delete or block messages from sources deemed offensive, he said.
China routinely blocks websites of Western media outlets, human rights groups, the Falun Gong spiritual group, Tibetan exiles and other sources of information it deems politically sensitive or harmful.
China, which has embraced the Internet as a tool of commerce and education, issued a raft of new regulations last year governing news, website content, chat rooms and email.
In October it published sweeping new regulations on Internet companies, limiting foreign investment and content and requiring strict surveillance against "subversive" content.
But groups including dissidents and Falun Gong - banned in China as an evil cult - have used proxy addresses and other sophisticated methods to overcome Internet site blocks.