Data posted on Google's website shows its services in China became largely inaccessible beginning around 1 a.m. PST Friday. That would be about 5 p.m. Friday in Beijing.
A Google Inc. spokeswoman says the company found no problems in its own computer or network that would disrupt its services in China.
That raised the possibility that China's Communist government decided to block Google's services at a politically sensitive time. Restricting access to Google's search engine might make it more difficult for people in China to find information about the candidates vying to steer the ruling party during the next decide.
Another search engine called Baidu is more widely used in China, but its results exclude content that the country's government deems objectionable.
Google, which is based in Mountain View, Calif., decided to stop censoring its search results in China in 2010. To avoid breaking the country's laws, Google moved the computers for its Chinese search engine from the country's mainland to Hong Kong, where the same censorship requirements aren't imposed.
Since Google took its stand against censorship, its search engine and other services have been periodically unavailable.
YouTube, Google's popular video site, has been blocked in China since 2009, according to the company.