LONDON - The United Kingdom (UK) and the United States have accused China of a global campaign of “malicious” cyber attacks in an unprecedented joint operation to reveal Beijing’s espionage.

Britain has publicly blamed China for targeting the Electoral Commission watchdog and for being behind a campaign of online “reconnaissance” aimed at the email accounts of MPs and peers.

Chinese spies are likely to use the stolen details to target dissidents and critics of Xi Jinping’s government in the UK, British intelligence services believe.

US officials said the APT31 hacking group spent more than a decade targeting the sensitive data of politicians, journalists, academics, dissidents and American companies.

The “prolific global hacking operation”, backed by the Chinese government, sought to “repress critics of the Chinese regime, compromise government institutions, and steal trade secrets,” US deputy attorney general Lisa Monaco said.

The hackers sent more than 10,000 “malicious” emails to the targets to gain access to personal information, US prosecutors said, adding the criminals threatened to “undermine democracies and threaten our national security”.

The US charged seven of the alleged Chinese hackers on Monday.

The UK said Beijing-linked hackers were behind the attack on the Electoral Commission which exposed the personal data of 40 million voters, as well as 43 individuals including MPs and peers.

A front company, Wuhan Xiaoruizhi Science and Technology Company, and two individuals, Zhao Guangzong and Ni Gaobin, linked to the APT31 hacking group were sanctioned in response to the hacks.

However, some of the MPs targeted by Beijing said the response did not go far enough.

They urged the Government to toughen its stance on China by labelling it a “threat” to national security rather than an “epoch-defining challenge”, and to put China in the “enhanced” tier under the Foreign Influence Registration Scheme.

The UK acted with support from allies in the Five Eyes intelligence-sharing partnership, which also includes the US, Canada, Australia and New Zealand, in identifying the Chinese-linked cyber campaigns.