One senior official said that the attack was traced back to china, however it is still not clear if it was planned by the Chinese government.Cyber Espionage is not new while China can point to the  Snowden documents revealing the U.S. spying on Huawei. in may, the Justice Department charged five members of a Chinese military group for carrying economical cyber espionage against US businesses.

Chinese hackers gains access to data on U S  Federal Employees    TechWorm - 48