Chinese hackers access US telecom firms, worrying national security officials

CNN —

A highly skilled group of Chinese government-linked hackers has in the last several months infiltrated multiple US telecommunications firms in a likely search for sensitive information bearing on national security, multiple sources briefed on the matter told CNN.

US investigators believe the hackers potentially accessed wiretap warrant requests, two of the sources said, but officials are still working to determine what information the hackers may have obtained. US broadband and internet providers AT&T, Verizon and Lumen are among the targets, the sources said.

US officials are concerned about the potential national security damage done by the hacking, which they only recently discovered. It’s the latest sophisticatedhacktargeting US federal agencies that investigators have linked to China, and it comes amid tensions between Washington and Beijing over cyber-espionage and other high-stakes national security issues.

In this June 4 photo, FBI Director Christopher Wray testifies during a Senate Appropriations Commerce, Justice, Science, and Related Agencies Subcommittee hearing on Capitol Hill in Washington, DC.

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As the backbone of internet and phone communications, US telecom firms hold enormous volumes of caller and user data. US law enforcement agencies request access, through a warrant, to specific portions of that data as part of criminal and national security investigations.

Some of those investigations would be of keen interest to Beijing. The US government has in recent years brought charges against Chinese government agents for allegedly harassing Chinese nationals on US soil and for hacking