China to close unregistered domestic Web sites

China soon will close unregistered domestic Web sites and blogs as the government tightens its grip on the Internet, a media watchdog said.

Beijing announced in March that every China-based Web site now had to register and provide complete information on its organizers by June 30 or face being declared illegal, the Paris-based media-advocacy group Reporters Without Borders (RWB) said in a statement released on Tuesday.

"The authorities also hope to push the most outspoken online sites to migrate abroad, where they will become inaccessible to those inside China because of the Chinese filtering systems," RWB said.

China is the world's second-largest Internet market, with about 100 million users. That number is growing.