The heads of 39 Chinese companies, which include Baidu and Alibaba, have agreed to stop the spread of "harmful information" after attending a three-day government workshop to discuss concerns about internet content.

The meetings were presided over by Wang Chen, director of the State Council Information Office, the government's propaganda and information arm. According to the BBC, the Xinhua news agency reported that all parties had agreed to "conscientiously safeguard the broadcasting of positive messages online."

During the discussions, which ended on Saturday, the heads of the 39 firms agreed to "strengthen self-management and self-discipline." According to the report they will "resolutely curb internet rumours, internet pornography, internet fraud and the illegal spread of harmful information" to mould the web into a "positive and beautiful spiritual home."

Chinese Industry and Information Technology minister Miao Wei also ordered internet companies to increase their investment in "tracking surveillance," highlighting the growing anxiety among Chinese top brass about the ever-increasing influence of the web. The boom in blogs, called Weibo in Chinese, and the potential they have to tear at the seams of government censorship with its 500-million plus internet users faces ever-increasing scrutiny.

Residents of China will not find these latest agreements surprising. The Chinese government has long fought to control the content viewable by its population, preferring instead to use the internet as a tool to spread propaganda and control oppression. In a country where freedom of speech is practically non-existent, the openness of the internet poses a huge risk to the control they exert on their people.

Last week the Chinese military were revealed by a U.S. congressional report as having been suspected by the U.S. government of hacking into two satellites in 2007 and 2008 via a satellite station located in Norway.