Google's decision to enlist the help of the National Security Agency in tackling cyber attacks has caused alarm among internet groups and bloggers, who fear that users' personal information could be accessed by the US government.

SHANGHAI, Jan 20 (Reuters) - In the autumn of 1998, computer science engineer Li Yanhong developed Rankdex, an experimental search engine that ranked websites according to their relevance to each other.

After last week's Google face-off with the Chinese government should western media companies be worried that they don't have a hope in the world's most populous country? It's quite simple, according to Siva Yam, the president of the US-China Chamber of Commerce, which principally represents the interests of American companies in China. "As long as you aren't involved in politics, the media or pornography, the government will leave you alone."

Yahoo knew it had been a target of sophisticated Chinese cyber attacks on U.S. firms before Google alerted the company to them, but remained silent while its bigger rival went public, a source familiar with the situation told Reuters.