The CBC's entire website as well as those of the Guardian, Spanish newspaper El Pais and French daily Le Monde were all unavailable in Beijing as of Wednesday at 5 p.m. ET.
The CBC's news story about the exposé, but not its entire website, was being blocked as early as the night before.
The website of the International Consortium of Investigative Journalists, which spearheaded the international joint investigation and obtained the leaked documents on which it was based, was also mostly unavailable.
Other news sites that did not prominently report the story, such as CNN and the BBC's main news page, were still viewable. However, a BBC story that mentioned the offshore disclosures was blocked.
"The authorities are not prepared to let that information be public," Fred Bild, Canada's former ambassador to Beijing, said in an interview last week anticipating what the Chinese government's reaction would be to the news.
Bild said the revelations would still filter through to mainland China, however.
"Even though they have extremely good methods of controlling the internet, if you have 500 million people conspiring to get information, there is no censorship that can really be absolute, and so it will get to be known very quickly."
President's family mentioned
The news outlets' reports included details of a real estate company co-owned by Chinese President Xi Jingping's brother-in-law, as well as British Virgin Islands corporations set up by former premier Wen Jiabao's son and son-in-law, plus dozens of more cases of people tied to high-level officials.
A wide array of Chinese nationals were found to be using offshore havens, including relatives of at least five current or former members of China's Politburo Standing Committee, the all-powerful group of seven (formerly nine) men who run the Communist Party and the country.
Sometimes the offshore accounts were for business purposes tied to the state entities they run, such as for direct foreign investments in Latin America, where Chinese companies have been expanding operations for years. But in many cases, the offshore shell corporations set up by Chinese nationals seemed to have no connection to state industries and are shrouded in questions that they refused to answer.
The discovery could incense ordinary citizens in China, where senior Communist officials used to enjoy a modestly better living but nothing close to the extravagant wealth required to stash money offshore, Bild said.
"Now, the income gap between the elite and the masses is huge.… You have hundreds of millions of people that are still living on very low income and they will be outraged," he told CBC News.
The CBC's website has been blocked before in China, notably for nearly four months in 2008. That prompted CBC president Hubert Lacroix to complain to the Chinese ambassador to Canada, following which access was restored.
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