U.S. officials say hackers with ties to the Chinese government are responsible for breaching the security of major telecommunications companies and U.S. agencies.

The latest hack, announced on Monday, The U.S. Treasury Department called the infiltration a “significant incident.”

Officials said the hackers were able to access employee workstations and some unclassified files. China denies involvement.

It is the latest in a series of cyberattacks targeting the United States and other Western targets in recent months.

The Treasury Department was hacked after news broke in late October that two major U.S. presidential campaigns had been compromised.

The FBI and Cybersecurity and Infrastructure Security Agency (Cisa) said the hack targeting White House events was carried out “by actors associated with the People’s Republic of China.”

In September, reports emerged of an operation that successfully breached the security measures of top telecommunications companies.

The White House recently said that at least nine companies have been hacked, including telecommunications giants AT&T and Verizon.

Earlier this year, in March, Seven Chinese citizens charged with hacking It lasted for at least 14 years and targeted foreign criticism of China, businesses and politicians.

China-related actions by Western governments have also targeted the UK Electoral Commission and the UK and New Zealand parliaments.

While full details have not been disclosed, the hacks appear to be the work of several different units — each of which U.S. authorities say is tied to the Chinese government.

Security companies have nicknames for these hacking groups. For example, the group behind the telecom hackers is best known as “Salt Typhoon,” which is the name given to it by Microsoft researchers. Other companies refer to it as “The Famous Sparrow,” “The Ghost Emperor” and “Earth Estri.”

Typhoon Yan is believed to be behind the telecommunications hacking attack. An independent group, nicknamed “Volt Typhoon”, Accused of breaking into critical infrastructure organizations to conduct potential sabotage attacks.

U.S. Justice Department officials linked the seven Chinese citizens accused of hacking to an operation called “Zirconium,” or “Trial of Panda.”

The UK’s National Cyber ​​Security Center said the same operation targeted emails from British MPs in 2021.

Recent hacks appear to be targeting powerful individuals and collecting data that could benefit the Chinese government.

Among them, they targeted calls from President-elect Donald Trump, Vice President-elect Vance and Vice President Kamala Harris’ campaign staff.

The hackers also accessed a database of phone numbers that had been tapped by law enforcement, information that experts say could be used to discover which foreign spies are being monitored.

The data of millions of Americans could have been compromised by an attack on a telecommunications company.

Richard Forno, assistant director of the Cybersecurity Institute at the University of Maryland, Baltimore County, said China’s efforts target multiple targets.

“This is more general information gathering, let’s see what we can get into and see what we can find,” he said.

U.S. lawmakers from both parties have expressed concerns about hacking attacks.

Democratic Senator Mark Warner called Typhoon Yan’s activity “the worst telecommunications hack in the history of our country.”

Brendan Kahl, Trump’s nominee to chair the Federal Communications Commission, said the intelligence briefing on the hack was “deeply concerning.”

“The information I heard made me want to smash my phone at the end,” he told CNBC.

FBI Director Christopher Wray recently said that Typhoon Yan’s hacking of telecommunications companies was China’s “most significant cyber espionage campaign in history.”

He has previously said China’s hacking program is “larger than all other major countries combined.”

In addition to charging seven Chinese citizens, U.S. authorities earlier this month warned China Telecom Americas, an American subsidiary of one of China’s largest communications companies, that it posed a threat to national security.

The company has 30 days to respond and could ultimately face a ban.

May, UK sanctions two individuals and Wuhan Xiaoruizhi Technology Co., Ltd.said to be related to “Judgement of the Panda”.

Mike Walz, Trump’s incoming national security adviser, said foreign hackers must face “elevated costs and consequences.”

Mr. Forno, of UMBC’s Cybersecurity Institute, said the hacks may have been years in the making.

“China has traditionally taken a very long-term and strategic view of how it conducts espionage and intelligence activities,” he said. “The United States tends to be more reactive and more interested in immediate results.”

Chinese Foreign Ministry spokesman Mao Ning told a news conference that the accusations were “baseless” and “lacked evidence.”

Mao Zedong said: “China has always opposed all forms of hacking and resolutely refuses to spread false information against China for political purposes.”

A spokesman for the Chinese Embassy said in a statement: “The United States needs to stop using cybersecurity to smear and slander China, and stop spreading all kinds of false information about the so-called threat from Chinese hackers.”