The U.S. and British governments on Monday accused China of carrying out extensive cyberattacks, imposing sanctions on two individuals and one company.

In a related development, the U.S. Justice Department said seven Chinese citizens, including the two, had been indicted for their involvement in a hacking group known as APT31 that engaged in an around 14-year operation that targeted government officials, companies, journalists, academics and others for sensitive information.

The sanctions were imposed on Wuhan Xiaoruizhi Science and Technology Company Ltd., which according to the U.S. Treasury Department is a front company of the Chinese Ministry of State Security, as well as Zhao Guangzong and Ni Gaobin.

U.S. and British officials said the two are affiliated with the Wuhan-based company and the hacking group connected to the Chinese government.

The United States is offering a reward of up to $10 million for additional information on the group and the individuals.

The British government, meanwhile, said the Chinese cyberattacks targeted the Electoral Commission, which holds the names and addresses of registered voters, and parliamentarians.

But it said the attacks did not have any impact on the democratic process or elections.

British Prime Minister Rishi Sunak said, "We've been very clear that the situation now is that China is behaving in an increasingly assertive way abroad, authoritarian at home, and it represents an epoch-defining challenge, and also the greatest state-based threat to our economic security."

"So, it's right that we take measures to protect ourselves, which is what we are doing," he said.

China said Tuesday it "firmly opposes" the "groundless unilateral" sanctions imposed by Washington and London, with Foreign Ministry spokesman Lin Jian vowing that Beijing will "take necessary measures to safeguard our lawful rights and interests."

Lin claimed the United States has encouraged the Five Eyes intelligence alliance also involving Australia, Britain, Canada and New Zealand to "compile and spread all kinds of disinformation" about the threats posed by the so-called Chinese hackers "driven by its own geopolitical agenda."

On Tuesday, New Zealand accused a Chinese state-sponsored group known as APT40 of "malicious cyber activity" targeting its parliamentary entities in 2021.

Judith Collins, minister responsible for the Government Communications Security Bureau, said the Chinese group was linked to an attack on the Parliamentary Counsel Office, which drafts laws, and another agency in charge of support for parliament.

Deputy Prime Minister and Foreign Minister Winston Peters confirmed senior government officials conveyed Wellington's concerns to the Chinese ambassador to New Zealand.

"Foreign interference of this nature is unacceptable, and we have urged China to refrain from such activity in future," Peters said in a statement.

The New Zealand Herald reported that some data was stolen from the system in the 2021 attack, but it was not of a strategic or sensitive nature, citing the bureau's analysis.

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