Google has said that issues affecting its popular Gmail service in China over the past few weeks appear to have been caused by government interference.
A spokesperson for the company explained that, despite a thorough investigation of the problems, Google had found no issues with its own infrastructure.
Widespread reports suggest that users in the region have had difficulty sending emails, accessing accounts and carrying out other tasks.
"There is no technical issue on our side. We have checked extensively. This is a government blockage carefully designed to look like the problem is with Gmail," a Google spokesman said.
The comments are the first time that Google has directly accused a government of interfering with its service, although suspicions of China's involvement in hacking, censorship and disruptive behaviour date back a long way.
The authorities in China already block YouTube, Facebook, Twitter and other sites allowing freedom of expression.
In 2010 Google moved its Chinese search business to Hong Kong to escape web censorship, in a move largely precipitated by a suspected state-sponsored hacking attack on its systems.
More recently, Google warned in a security blog on 11 March of "some highly targeted and apparently politically motivated attacks" against some of its users, although China was not specifically mentioned.
The Chinese authorities have been quick to clamp down on any possibility of the so-called 'Jasmine revolution' spreading from Middle East countries such as Libya and Egypt to south-east Asia.
Google has been criticised in the past for working with the Chinese authorities to censor specific search terms.
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