After blaming an internal technical glitch, Google now says it's not sure why people in China have had trouble using its search service.

Some people in China reported being unable to perform Google searches even though they could access the Google search page at, where the company is directing Chinese users.

Some observers thought the Chinese government had started blocking the site, but Google said the problems were due to a change the company had made to its servers.

"In the last 24 hours 'gs_rfai' started appearing in the URLs of Google searches globally as part of a search parameter, a string of characters that sends information about the query to Google so we can return the best result," Google said. "Because this parameter contained the letters rfa the great firewall was associating these searches with Radio Free Asia, a service that has been inaccessible in China for a long time, hence the blockage."

However, later in the day Google reversed course. "Having looked into this issue in more detail, it's clear we actually added this parameter a week ago. So whatever happened today to block must have been as a result of a change in the great firewall," the company said.

Still, for some reason search traffic in China is now back to normal, without any changes on Google's end. "We will continue to monitor what is going on, but for the time being this issue seems to be resolved," the company said.

Google said in January that it would stop censoring its search results in China after discovering the theft of some of its intellectual property during a cyberattack originating in the country, and learning that the Gmail accounts of some human rights advocates had been broken into.

It closed the censored version of its search service last week, redirecting visitors to its Hong Kong-based site. Since then, observers have wondered how the Chinese government will react because people in China can now find uncensored results from the Hong Kong site.