The data itself was stored on an unclassified network, but the officials who talked to the Post said that when all of the data that was stolen was put together the result would be considered classified.
The hackers, according to the Post, also stole plans for a supersonic anti-ship missile for use on USA submarines with the breaches taking place in January and February.
The hackers took 614 gigabytes of material related to a closely held project known as Sea Dragon, as well as signals and sensor data, submarine radio room information relating to cryptographic systems, and the Navy submarine development unit's electronic warfare library.
The U.S. Navy and the FBI are investigating a massive hack attack on a Navy contractor, CBS News national security correspondent David Martin has confirmed.
The Navy is leading the investigation into the breach-that occurred in January and February-with the assistance of the FBI, US officials said on Friday.
The impact of the hack on USA naval capabilities has been evaluated by the Pentagon's Damage Assessment Management Office, which has refused to comment on its findings, however. Bill Speaks was quoted as telling the Post.
Hirono, Deutch Renew Effort to Strengthen and Expand Social Security
Unless lawmakers act, both programs face the prospect of being unable to cover the full cost of promised benefits . About a quarter of Part B costs are paid for by beneficiary premiums with the rest from the federal budget.
"It would be inappropriate to discuss further details at this time", he added. The officials refused to identify the contractor, and upon the Navy's request, the newspaper also agreed to withhold some details about the hack, citing national security as the reason to do so.
It also comes as President Donald Trump continues to court Beijing in his efforts to denuclearize North Korea. US officials have always been anxious that ZTE equipment could be used by the Chinese government for espionage or sabotage.
Investigators told the Post that the Chinese Ministry of State Security, a civilian spy agency, carried out the hack.
The little information the Pentagon has released about Sea Dragon says the program has the capacity to introduce "disruptive offensive capability" by 'integrating an existing weapon system with an existing Navy platform'.
According to the Post, the Sea Dragon project was created by the Pentagon in 2012 to adapt existing USA military technologies to new applications.