In the latest accusations of cyber-warfare against China, the web giant Google claims that Chinese hackers broke into the personal Gmail accounts of hundreds of Asian and US government officials, as well as military personnel, journalists and political activists.
It is the second time in 17 months that Google has accused China of attempting to hack into Google's network.
"We recently uncovered a campaign to collect user passwords, likely through phishing," Google's security team engineering director Eric Grosse said in a blog posting.
The US company said that its security was not breached but added that individuals' passwords were obtained through fraud. Google said the victims have been notified and their Gmail accounts secured.
"This campaign, which appears to originate from Jinan, China, affected what seem to be the personal Gmail accounts of hundreds of users including, among others, senior US government officials, Chinese political activists, officials in several Asian countries (predominantly South Korea), military personnel and journalists," Google said.
The White House believes that no key security breach took place, but the FBI and Homeland Security in the US are investigating the incidents.
Jinan is the capital of Shandong province and is home to the Lanxiang Vocational School, which was one of two educational facilities linked to a number of cyber attacks last year. Lanxiang says that it is a vocational school that trains hairdressers and chefs, and insists its expertise is in vehicle maintenance and repair.
It advertises for students on TV, and claims it has the biggest computer laboratory in the world, a boast it says is confirmed by Guinness World Records. Jinan is also home to one of six technical reconnaissance bureaus of the People's Liberation Army.
China has repeatedly denied any involvement in internet attacks, saying it is opposed to hacking and has a consistent policy aimed at stopping cyber-attacks. It stoutly denied Google's claims yesterday, saying it "could not accept" the accusations. A Chinese foreign ministry spokesman, Hong Lei, told a news briefing: "Blaming these misdeeds on China is unacceptable. Hacking is an international problem and China is also a victim. The claims that China supports this kind of hacking are without any basis in fact, and there is another motive at work."
Google said most account hijackings were not very targeted and were designed to steal identities or financial data, or send spam.
"But some attacks are targeted at specific individuals. The goal of this effort seems to have been to monitor the contents of these users' e-mails, with the perpetrators apparently using stolen passwords to change peoples' forwarding and delegation settings," it said.
Google has had a fragile relationship with China for years. Although it is the second-biggest search engine in China, it heavily trails the market leader, Baidu. Last year, Google threatened to pull out of China completely because of censorship and a sophisticated hacking assault originating from China in late 2009 and early last year.
Google went public about the attacks and, being true to its "Don't Be Evil" motto, said it was scaling back its operations in China. The company said it was no longer prepared to censor content that the government did not want the public to see.
China has tens of thousands of security officials working at monitoring the internet - the so-called "Great Firewall of China" - and more than a dozen ministries and agencies are involved in enforcing the rules.
China has said the regulations are aimed at stopping pornography and other content it considers harmful. Critics, however, believe they are used to stop dissent.
Last year, Google shifted its Chinese-language search engine from China's mainland. It now is based in Hong Kong, which is not subject to Beijing's censorship rules.
