In January and February 2018, the computers belonging to a U.S. Navy contractor were compromised by hackers backed by the Chinese government – As a result, highly sensitive data was accessed and stolen.

The stolen data was related to undersea warfare and includes classified information on future plans regarding the development of supersonic anti-ship missile supposed to be used on U.S. submarines by 2020, reports The Washington Post.

The targeted contractor according to unnamed U.S. officials works for the Naval Undersea Warfare Center (NUWC), a full-spectrum research, development, test and evaluation, engineering and fleet support center for submarines, autonomous underwater systems, and offensive and defensive weapons systems associated with undersea warfare.

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The initial investigation showed that hackers stole a massive 614 gigabytes of data stored on the contractor’s unclassified network. The data was related to an ongoing project called 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 Post reported.

However, the Washington Post has refrained from publishing further details about the breach and agreed to withhold specific details about the compromised missile project on the request of Navy since investigations are underway.

The cyberwar between China and the United States has been going on for years, previously, the National Security Agency (NSA) hacked three major cell phone operators in the hunt for millions of SMS data.

In May 2013, Chinese hackers gained access to a sensitive weaponry system of United States. In the attack, more than 24 key systems for weapons were affected including systems for fighter jets, missile defense, navy vessels and helicopters.

In March this year, the APT15 hacking group known to be associated with Chinese intelligence was blamed for stealing secret information related to the UK’s military technology by compromising computer of a UK government contractor and launching a malware-based attack.

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