According to a new report from security firm Mandiant, network intrusions originating in China have become quite commonplace; with at least 141 companies across 20 industrial sectors having been compromised by one single hacking organization based in Shanghai.

The Mandiant report reveals the worldwide accomplishments of a professional hackers' group called APT1; and is based on convincing proof that APT1 is actually part of People's Liberation Army Unit (PLA Unit) 61398. The mentioned PLA Unit is an organization which is reportedly interested in pilfering data from the US companies rather than just defacing or deleting the data.

Despite the fact that APT1 - which gain access to the networks of companies via targeted attacks and social engineering - does not have any fixed street address, the PLA Unit 61398 is situated in a 12-story office building along Datong Road in Shanghai; a location which is not exactly open to public inspection.

Against the backdrop of the Mandiant report, CNET has pointed out that the evidence which links APT1 and the Chinese military is that the PLA Unit 61398 is, as per public records, a part of the PLA's General Staff Department's third department (second bureau).

Meanwhile, the Project 2049 Institute - a think tank which has close ties to US conservatives - is of the opinion that the PLA Unit 61398 is China's "premier entity targeting the US and Canada, most likely focusing on political, economic, and military-related intelligence."