Beijing, Apr 16 (IANS): The rapid development of internet has brought conveniences and efficiency to information exchanges, but has also speeded up the spread of rumours, Xinhua reported citing a Chinese daily.

Society should remain on high alert against the exponential growth of online rumours as the harm could be huge, it said.

Online rumours are usually created to defame someone or to spread false information about public events. These rumours not only infringe upon others' interests, but also pose a threat to social stability, said a People's Daily article published Monday.

China has removed over 210,000 online posts since mid-March and shut down 42 websites in its crackdown on internet-based "rumour-mongering", a senior official said April 12.

The move came after Bo Xilai, a rising star on the Chinese political scene, was demoted from the country's powerful Communist Party politburo after police named his wife as a prime suspect in the murder of a British businessman.

Bogu Kailai, whose husband Bo Xilai, 62, had been tipped as a future leader of China, is being investigated over the death of Neil Heywood. He died in November.

Bo was dismissed as party chief of the southwest city of Chongqing last month after his police chief spent over an hour in the city's US consulate in an apparent asylum bid.

The People's Daily said that rumours that target celebrities, social ethics and basic social systems could be the most harmful, as they undermine public confidence in the government, society and political system.

They can cause serious ideological confusion and affect people's confidence in China's reform and development process, it said.

The Chinese government recently initiated a campaign to clean up fabricated online information on microblogs after "rumours stirred worries about the country's political situation".

Police in Beijing detained six people last month for allegedly fabricating and spreading rumours about "military vehicles entering Beijing" and something "wrong" happening in the capital, reported the state-run Xinhua news agency.

The People's Daily, the flagship newspaper of the Communist Party of China Central Committee, Monday listed 10 "infamous" rumours that have caused major social panic in recent years.

One of the rumours was an online post complaining of "a salt shortage" after a tsunami crippled Japan's Fukushima Daiichi nuclear power plant, triggering panic buying and table salt hoarding across China amid radiation fears.

The "salt" farce not only affected market order and people's lives, but also became an "international joke" that damaged the national image, the newspaper said.

China, it said, is at a stage of rapid social transformation, and social problems and contradictions are frequently emerging. Online rumours fabricate, exaggerate or distort events by exploiting public hatred toward graft, uneven income distribution and the abuse of public rights, and some people have vented their negative emotions by passing on these rumours.

Therefore, clearing up the roots and causes of these rumours is crucial to curbing rumours online, the daily added.

Authorities should release information with detailed facts immediately after rumours begin to circulate, it said.