China shut down 162 sites offering pornographic audio or video files for operating without a broadcast permit, the official Xinhua news agency said.

China has closed more than 2,000 Web sites and arrested at least 45 people in a sting against online porn launched in January. It has also vowed to stamp out erotic text messages sent on cell phones. Various blog hosts have been shut down as well, including some known for political content that ran against the central government line.

Web domain owners were also ordered Monday not to broadcast movies or television shows before that had not undergone government censorship and approval, according to an online statement from China's State Administration of Radio, Film and Television.

The crackdown comes a week after access to YouTube was blocked in most of the country.

No reason was given for the move and Foreign Ministry spokesman Qin Gang [cq] last week said the government "is not afraid of the Internet," however YouTube remained blocked on Tuesday.