Ellen Nakashima writes the suspected hackers remain unidentified and that it is unclear whether the people have real connection with the OPM attack.
Officials believe the hackers were contractors for China’s ministry of state security and went out of their way to conduct cyber attacks against OPM to mine data, according to the report.
Chinese officials denied claims that the breach was state-sponsored and described it as a criminal activity, the Post reports.
The OPM breach compromised personal, financial and biometric data that belong to more than 22 million existing and former federal employees.