Beijing launched the campaign this summer, arresting dozens of people for spreading rumors, creating new penalties for people who post libelous information and calling in the country's top bloggers for talks urging them to guard the national interest and uphold social order. At the same time, government agencies at all levels have boosted their online presence to control the message in cyberspace.

"If we should describe the online environment in the past as good mingling with the bad, the sky of the cyberspace has cleared up now because we have cracked down on online rumors," Ren Xianliang, vice minister of the State Internet Information Office, said during a rare ...