Chinese authorities have made Google’s services largely inaccessible in recent days, a move most likely related to the government’s broad efforts to stifle discussion of the 25th anniversary of the crackdown on pro-democracy demonstrators in Tiananmen Square.

In addition to Google's search engines being blocked, the company's products, including Gmail, Calendar and Translate, have been affected. This is not the first time China has taken aim at Google and its users there. The authorities blocked Google for 12 hours in 2012, according to GreatFire.org, an independent censorship-monitoring website, which published a blog post about the recent problems Monday. But the recent crackdown has been more severe, and there has been no indication of how long it will last.

“This is by far the biggest attack on Google that’s ever taken place in China,” said a co-founder of GreatFire.org, who asked to remain anonymous to prevent retaliation by the authorities. “Probably the only thing comparable is when the Chinese government first started blocking websites in the 1990s.”

While internet users in mainland China could reach international versions of Google search until a few days ago, “all Google services in all countries, encrypted or not, are now blocked in China,” GreatFire.org said in the blog post. These include the Chinese-language version based in Hong Kong, Google.hk, and Google.com, Google Australia and others.

Other services with no direct search function, including the company’s Picasa photo program, maps service and calendar application, were also inaccessible to most users Monday. “It is the strictest censorship ever deployed,” the blog said.

Unlike the websites of Facebook, YouTube, Twitter and The New York Times, which are reliably blocked by the authorities, Google services have been disrupted in a way that affects about 9 of 10 Chinese users, according to GreatFire.org. By allowing some access, "the Chinese government is trying to pin the blame on Google," the GreatFire co-founder said.

Google said that it was not the problem. “We’ve checked extensively, and there are no technical problems on our side,” said a Google spokeswoman, who declined to elaborate.

NYT