The Federal B ureau of Investigation was investigating allegations by Internet giant Google that Chinese hackers were behind the hacking of hundreds of Gmail accounts, including those of senior US officials, the White House said.
"US President Barack Obama is aware of it and is being updated on regularly," White House Press Secretary Jay Carney told reporters at his daily news conference.
"Threats to information and communications infrastructure pose a serious economic and national security challenge for the US and our partners, which is why the president has made cyber security one of his top priorities," he said.
"As with all intrusions, we employ an all-of-government approach with the appropriate agency in the lead. In this case, the FBI is coordinating a response. We're obviously aware of these reports. We're looking into these reports.
As of now, he said, there has been no impact on the US government policy, with regard to work emails, which is driven by the Presidential Records Act.
"So the issue in terms of our work accounts, there we have no evidence to suggest that any of those accounts were accessed or compromised."
Secretary of State Hillary Clinton also expressed her deep concern over the issue.
"We are obviously very concerned about Google's announcement regarding a campaign that the company believes originated in China to collect the passwords of Google email account holders," she said, adding that Google informed the State Department of this situation yesterday in advance of its public announcement.
"These allegations are very serious. We take them seriously, we're looking into them, and because this will be an ongoing investigation, I would refer you to first Google for any details that they are able to share at this time and to the FBI, which will be conducting the investigation," she said.