China-based hackers have launched an unprecedented cyber-attack on the Canadian government, penetrating the computer systems of two key agencies and forcing them offline, CBC reported.
Asked about the report, the Treasury Board issued a brief statement recognizing it had detected an "unauthorized attempt to access its networks," but did not elaborate.
"Employee access to the Internet has been limited for the time being," said Treasury Board spokesman Jay Denney.
CBC News cited "highly placed sources" in conservative Prime Minister Stephen Harper's government as saying that the cyber-attacks, first detected in January, were traced to computer servers in China.
China on Thursday rejected as "groundless" the reports suggesting it was behind the unprecedented cyberattack on the Canadian government.
"The allegation that the Chinese government supports Internet hacking is groundless," foreign ministry spokesman Ma Zhaoxu told reporters during a regular briefing.
"The Chinese government attaches importance to the safety of computer networks and asks computer and Internet users to abide by laws and regulations."
The hackers managed to penetrate the computer systems at the Finance Department and the Treasury Board, according to CBC. They also successfully overpowered computers in the offices of senior government officials in a bid to steal passwords that hold the key to government data systems.
Although CBC said it could not determine whether the attackers were Chinese or simply other nationals who used China-based servers, CTV television said they were "Chinese government hackers."
It cited sources as saying the Canadian Security Intelligence Service has advised government officials not to name China as the origin of the attacks, or even discuss the matter.
Chinese espionage has become a "major problem" for Canada and other countries, a senior government official told CTV.
CBC said it remained unclear whether the attackers were able to access other computer networks, such as those containing Canadians' tax and health records along with other personal details.
Upon learning of the attack, Canadian cybersecurity officials shut down Internet access at the two departments as they scrambled to prevent hackers from stealing more information via the Internet, it added.
"There are no indications that any data relating to Canadians was compromised by this unauthorized attempt to access the TBS (Treasury Board of Canada Secretariat) network," said Denney.
"The government of Canada has plans in place to prevent, minimize and address the impacts of cyber threats."
Several governments have pointed to the growing threat of Chinese espionage online.
Last week, US computer security firm McAfee said hackers from China had penetrated computer networks of global oil companies, stealing financial documents on bidding plans and other confidential information.
The United States has created its own Cyber Command, while NATO leaders agreed in November to enshrine cybersecurity as one of the 28-nation military alliance's priorities.
In January 2010, Google said it had fallen victim to attacks by China-based cyber spies apparently intent on hacking into the Gmail accounts of Chinese human rights activists. The attack touched off a huge battle with Beijing on censorship.
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