Administration Hit By Major Data Breach

The Associated Press reports that the Obama administration is scrambling to assess the impact of a massive data breach that occurred when federal agencies were hacked.

A congressional aide familiar with the situation, who declined to be named because he was not authorized to discuss it, says the Office of Personnel Management (OPM) -- the agency that handles security clearances and employee records -- and the Interior Department were hacked. A second U.S. official who also declined to be identified said the data breach could potentially affect every federal agency.

OPM released a statement saying that the incident potentially affected "personnel data for current and former federal employees, including personally identifiable information (PII). The number affected could be "approximately 4 million individuals," the statement read.

A statement from the Department of Homeland Security (DHS) appeared to confirm the hack, saying that the agency used cyber indicators to detect malicious activity affecting the information technology systems and data in April 2015. At the beginning of May, DHS concluded that OPM's data had been compromised.

"DHS is continuing to monitor federal networks for any suspicious activity and is working aggressively with the affected agencies to conduct investigative analysis to assess the extent of this alleged intrusion," the agency said in a statement.

In addition to the 4 million individuals being notified by OPM, the agency said additional notifications could become necessary as the investigation continues. It is offering credit report access, credit monitoring and identify theft insurance and recovery services to potentially affected individuals through a company called CSID.

Separately, the FBI said it is investigating the issue.

The White House was considering a public announcement of the breach Thursday night or Friday morning, an official told the Associated Press.

The Office of Personnel Management is the human resources department for the federal government, and issues security clearances.

CBS News' Jeff Pegues and Arden Farhi contributed to this report.

CBS/AP