Just three weeks after the U.S. Department of Justice indicted five members of China’s People’s Liberation Army (PLA) Unit 61398 for cyber espionage, the cybersecurity firm Crowdstrike has released what it says is evidence of a second Chinese PLA unit spying on Americans. The group, identified as Unit 61486, is suspected of targeting American, European, and Japanese companies involved with satellite, aerospace, and communications industries.

The revelations add further evidence that a primary aim of Chinese espionage is to obtain commercial and military secrets, a claim the Chinese government denies. The five PLA officials indicted in May are accused of hacking into computer files at major industrial firms such as Alcoa and Westinghouse, where the intrusions allegedly committed “substantial” damage.

In a report released Monday, Crowdstrike described how Unit 61486 penetrated confidential computer networks through “spear phishing”, a process in which hackers embed malware in innocent-seeming emails. (One email, for example, included a link to a yoga studio in Toulouse, France) Crowdstrike nicknamed the group “Putter Panda” because many of the malicious emails were sent to golf-playing victims.

For the United States, Crowdstrike’s revelations -- like the February 2013 findings by Mandiant that led to the May indictment -- provide valuable insight into what information, exactly, Beijing is seeking to obtain. But Washington’s policy options are limited. China, which has accused the United States of widespread espionage of its own, reacted angrily to the Department of Justice action, and the five indicted PLA officials are unlikely to stand trial in the U.S.

In the meantime, Crowdstrike’s revelations are likely to escalate tensions between the world’s two largest economies, which this year have tussled over China’s assertive military behavior in its maritime periphery. In addition, already-strained relations between Beijing and Tokyo may worsen with evidence of Chinese hacking into Japanese national security entities. Regional security in East Asia -- tenuous at the best of times -- has just become even shakier.