U.S. officials reportedly suspect China’s involvement in the hack.
A massive breach has exposed the personal information of as many as 4 million federal employees.
The Associated Press published its story of a large-scale breach of federal personnel data just after 5 p.m. on June 4, saying the Obama administration had been mulling a public announcement later in the evening or Friday morning.
The Office of Personnel Management issued a press release minutes after the AP report, saying the personally identifying information of as many as 4 million individuals had been potentially exposed in a breach.
Unnamed federal officials told the Associated Press that OPM and the Interior Department were hacked, and OPM has promised credit monitoring for the affected individuals.
The National Treasury Employees Union, which represents some 150,000 employees across 31 different agencies, said that NTEU officials were briefed by OPM on June 4, and that "it is vital to know as soon as possible the extent [of the breach] so that affected employees can be notified promptly and encouraged to take all possible steps to protect themselves."