China's Sina drops Google search service

China's largest Internet portal Sina said Tuesday it has replaced Google's search service on its websites with its own technology, further denting the US giant's presence in the Asian nation.

"Our contract (with Google) ended this month and the whole websites are now using our own search technology," Liu Qi, a spokesman for Sina, told AFP, adding the Chinese firm no longer had any cooperative agreements with Google.

The US web giant has been losing search engine market share in China since January last year, when it said it was no longer willing to self-censor content to comply with government rules.

The company said it had suffered cyberattacks from China-based parties apparently intent on hacking into the Gmail accounts of rights activists.

The resulting row caused tensions to spike between China and the United States, and ended with Google automatically re-routing users of its mainland search engine to its uncensored site in Hong Kong.

The web giant has since tweaked the way it re-routes Internet users in order to renew its business licence in China, which has the world's largest online population, estimated at more than 450 million people.

But last week Google again accused China of interfering with its Gmail service, calling it "a government blockage carefully designed to look like the problem is with Gmail".

China has denied any state involvement in both issues.

The disputes have hurt Google's business in China, with its Internet search market share dropping to 19.6 percent in the fourth quarter last year from 21.6 percent in the previous three months, Chinese Internet research firm Analysys International says.

Its local rival Baidu, meanwhile, represented 75.5 percent of China's online search market in the same period.