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US warns victims of 'Chinese' data hack US warns victims of 'Chinese' data hack
(35 minutes later)
Four million current and former US government employees are being told to take precautions after having personal information stolen by cyber hackers.Four million current and former US government employees are being told to take precautions after having personal information stolen by cyber hackers.
Chinese perpetrators are suspected of carrying out a "massive breach" of the personal data, officials said.Chinese perpetrators are suspected of carrying out a "massive breach" of the personal data, officials said.
Employees have been told to monitor or close bank accounts, freeze credit reports, and change online passwords.Employees have been told to monitor or close bank accounts, freeze credit reports, and change online passwords.
Some have spoken to the BBC expressing fears over how their personal information will be used.Some have spoken to the BBC expressing fears over how their personal information will be used.
"Identity theft is one thing I'm concerned about," said Bryan Sivak, a former technology officer with the Department of Health and Human Services."Identity theft is one thing I'm concerned about," said Bryan Sivak, a former technology officer with the Department of Health and Human Services.
"But depending on what information was accessed, I'm more worried about this information being used to illegally access various networks or against individuals directly.""But depending on what information was accessed, I'm more worried about this information being used to illegally access various networks or against individuals directly."
Mr Sivak said he had not yet been notified if his personal data has been exposed, but another employee told the BBC they had already received instructions.Mr Sivak said he had not yet been notified if his personal data has been exposed, but another employee told the BBC they had already received instructions.
J David Cox Sr, president of the largest union representing federal employees, says he "will demand accountability" and push for the information to be secured.J David Cox Sr, president of the largest union representing federal employees, says he "will demand accountability" and push for the information to be secured.
The Office of Personnel Management (OPM) OPM said it became aware of the breach in April during an "aggressive effort" to update its cyber security systems.The Office of Personnel Management (OPM) OPM said it became aware of the breach in April during an "aggressive effort" to update its cyber security systems.
It said it would be offering those affected 18 months of free credit monitoring and identity theft insurance.It said it would be offering those affected 18 months of free credit monitoring and identity theft insurance.
OPM serves as the human resource department for the federal government. The agency issues security clearances and compiles records of all federal government employees.OPM serves as the human resource department for the federal government. The agency issues security clearances and compiles records of all federal government employees.
Information stored on OPM databases includes employee job assignments, performance reviews and training, according to officials.Information stored on OPM databases includes employee job assignments, performance reviews and training, according to officials.
What was stolen?
An unnamed US official told the Reuters news agency that some of the stolen information includes security clearances and background checks from as far back as 1985.
"This is deep. The data goes back to 1985. This means that they potentially have information about retirees, and they could know what they did after leaving government," said the official, speaking on condition of anonymity.
Some of the sensitive personal information could be used to access critical weapons systems, according to the official.
Susan Collins, a member of the Senate Intelligence Committee, said the hackers were believed to be based in China.Susan Collins, a member of the Senate Intelligence Committee, said the hackers were believed to be based in China.
But China denied there was any official involvement in the attack.But China denied there was any official involvement in the attack.
A spokesman for the Chinese embassy in Washington called the allegations "not responsible, and counterproductive".A spokesman for the Chinese embassy in Washington called the allegations "not responsible, and counterproductive".
Previous hack attacks on US government
The FBI and the Department of Homeland Security are investigating the latest breach.The FBI and the Department of Homeland Security are investigating the latest breach.
Ken Ammon, chief strategy officer of Xceedium - a cyber security firm - warned that the hacked data could be used to impersonate or blackmail federal employees with access to sensitive information.Ken Ammon, chief strategy officer of Xceedium - a cyber security firm - warned that the hacked data could be used to impersonate or blackmail federal employees with access to sensitive information.
Congressman Adam Schiff has called for cyber databases to be upgraded saying that "a substantial improvement in our cyber databases and defences is perilously overdue".Congressman Adam Schiff has called for cyber databases to be upgraded saying that "a substantial improvement in our cyber databases and defences is perilously overdue".