A highly sophisticated cyberattack against Canada's National Research Council infiltrated a system that contained personal information, the privacy commissioner's office said Thursday.

Canadian officials have put the blame on the attack on the Chinese government. 

The privacy commissioner was first informed of a security breach on July 23 and was told on Monday that the personal data was in fact exposed.

A spokesperson for the ministry told CTV News that while the attack is a "serious security issue," the full extent of the breach is not yet known.

"We are following developments very closely due to the potential implication for personal information," Tobi Cohen said in a statement on Thursday.

China, meanwhile, has accused Canada of making "baseless accusations." 

China’s foreign ministry spokesperson Qin Gang said Thursday that the Chinese government “consistently opposes criminal activities” aimed at sabotaging computer networks, “and has been cracking down on such activities firmly.”

Gang made the comments in response to a reporter’s question about Canada’s claims.

“It is irresponsible for the Canadian side to make groundless accusations against China when there is no credible evidence. We are strongly opposed to that. We urge the Canadian side to correct their mistakes, stop making baseless accusations and redress the negative impacts incurred by their statement.”

The statement comes two days after the NRC confirmed a CTV News report that a “highly sophisticated Chinese state-sponsored actor” had targeted the agency’s computer systems over the last month.

NRC president John McDougall said that the “highly sophisticated” cyberattack may have compromised scientific and industrial trade secrets and told employees not to to plug memory sticks, smartphones or tablets into their computers.

The NRC is Canada’s leading science and technology agency. It conducts research into satellites, space and industrial innovations, and genetically modified foods, among other areas.

As a precaution, the NRC’s computer networks have been isolated from the government’s IT network, the Treasury Board said.

“We have no evidence that data compromises have occurred on the broader Government of Canada network," a Treasury Board statement said Tuesday. The agency added that it could take security experts up to a year before a more secure computer system could be put in place.

Foreign Affairs Minister John Baird, who was on a three-country tour through Asia earlier this week, raised the matter with his counterpart in Beijing during “full and frank discussions,” CTV’s Ottawa Bureau Chief Robert Fife reported on Tuesday.

This is not the first time Chinese hackers have penetrated Canadian government computers. They have previously targeted the Finance department, the Treasury Board, the Bank of Canada, and even the email accounts of members of Parliament.

With a report from CTV’s Ottawa Bureau Chief Robert Fife