The Department of Justice has accused China of sponsoring hackers who are targeting labs developing Covid-19 vaccines.
US officials have charged two Chinese men who allegedly spied on American companies doing coronavirus research and got help from state agents for other thefts.
The indictment comes amid a US crackdown on Chinese cyber espionage.
The US, UK and Canada last week accused Russia of seeking to steal research related to Covid-19.
The accusations against former electrical engineering students Li Xiaoyu and Dong Jiazhi released on July 21 include charges of trade secret theft and wire fraud conspiracy.
Prosecutors said the two men spied on a Massachusetts biotech company in January which was known to be researching possible cures for Covid-19. They also hacked a Maryland company less than a week after it said it was researching Covid-19.
Officials called the Chinese men private hackers who occasionally received support from Chinese intelligence agents, including an officer from the Chinese Ministry of State Security (MSS).
Li Xiaoyu and Dong Jiazhi previously stole “hundreds of millions of dollars’ worth of trade secrets, intellectual property, and other valuable business information” beginning in 2009, prosecutors alleged.
The indictment unsealed in Washington state said Li Xiaoyu and Dong Jiazhi – who reside in China – recently “researched vulnerabilities in the networks of biotech and other firms publicly known for work on Covid-19 vaccines, treatments, and testing technology”.
Countries where companies were targeted include Australia, Belgium, Germany, Japan, Lithuania, the Netherlands, Spain, Sweden and the UK.
According to the indictment, the hackers were able to infiltrate a British artificial intelligence firm, a Spanish defense contractor, and a Australian solar energy company.
Prosecutors said the men at times acted in their own self-interest – including one occasion when they demanded a ransom from a company in exchange for not releasing its private information – but at other times “were stealing information of obvious interest” to the Chinese government.
According to the indictment, the hackers “worked with, were assisted by, and operated with the acquiescence of” the MSS.
Li Xiaoyu and Dong Jiazhi allegedly stole military data and provided the Chinese government with the passwords of a democracy activist in Hong Kong and a former Tiananmen Square protester.