The US justice department has indicted two Chinese men accused of hacking into the computer networks of companies and government agencies in Western countries.
The pair are allegedly part of a “hacking group” known as Advanced Persistent Threat 10, affiliated with China’s main intelligence service.
They have not been arrested.
The UK, Australia, Canada, Japan, the Netherlands, New Zealand and Sweden were also reportedly targeted.
The UK government said it was joining allies in holding the Chinese government responsible for a global campaign targeting commercial secrets.
Zhu Hua and Zhang Shilong worked for a company called Huaying Haitai and in association with the Chinese Ministry of State Security, the US court filing says.
US corporations involved in aviation, space and satellite technology, and government agencies including the Navy and the space agency Nasa were targeted, it adds.
Announcing the unsealing of the indictments, US Deputy Attorney General Rod Rosenstein said China had violated a 2015 agreement under which it had pledged to not engage in commercial cyber-spying.
Mr Rosenstein said his department’s move had been co-ordinated with US allies in Europe and Asia to rebuff “China’s economic aggression”.
He added: “We want China to cease its illegal cyber activities.”
FBI Director Christopher Wray said the two men were at present “beyond US jurisdiction”.
UK Foreign Secretary Jeremy Hunt said: “This campaign is one of the most significant and widespread cyber intrusions against the UK and allies uncovered to date, targeting trade secrets and economies around the world.
“These activities must stop. They go against the commitments made to the UK in 2015, and, as part of the G20, not to conduct or support cyber-enabled theft of intellectual property or trade secrets.”