Bloomberg said it believes its English-language website and its Business Week site were blocked on Friday by Chinese authorities after it published details about the multi-million dollar fortunes of Vice President Xi Jinping's extended family.

Beijing will hold a once-a-decade leadership transition this year during which Communist Party chief, President Hu Jintao, and Premier Wen Jiabao will hand power to a younger group of leaders, headed by the party chief heir apparent Xi.

The government is determined to guard against any signs of discontent that could escalate into broader protests and threaten the Party's authority as the new generation takes over amid destabilising scandals and economic uncertainties.

In an emailed statement, Bloomberg spokeswoman Belina Tan said: "Our website is currently inaccessible in China in reaction, we believe, to a Bloomberg News story that was published on June 29."

She would not comment on whether Bloomberg was in talks with the government over the issue, but said "there is no impact" to the company's other services, including terminal feeds used by clients to access economic data and news.

Asked at a foreign ministry briefing last week about the blocked websites, a ministry spokesman did not respond directly but said all websites must abide by China's laws.

In its article, Bloomberg stated that no assets were traced to Xi, his wife or their daughter, adding there was no indication Xi intervened to advance his relatives' business transactions, or of any wrongdoing by Xi or his extended family.

Privately-held Bloomberg competes with Thomson Reuters, Dow Jones & Co, a unit of News Corp, and other news and data providers.

China's blocking of websites and censorship of search results for politically sensitive terms is known colloquially as the "Great Firewall of China", though some Internet users have skirted restrictions by using code words.

Government censors ban numerous overseas websites, including Facebook, Twitter and YouTube, and some foreign media outlets, fearing that sharing of images and information could cause social instability and harm national security.

(Reporting by Michael Martina; Editing by Ken Wills, Ian Geoghegan and Dean Yates)

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