China represents an increasing threat to the US power grid, lawmakers were told Tuesday during a hearing in which they were warned a cyberattack from the nation could plunge military and other sensitive sites into darkness.

“The Chinese activities are quite alarming,” said Manny Cancel, senior vice president of the North American Electric Reliability Corp., during testimony before a US House subcommittee.“Chinese cyber activities are one of the most dynamic cyber threats. China continues to demonstrate increasing sophistication, including new and adaptive techniques to gain access to networks.”

The hearing, held by the House Energy and Commerce Subcommittee on Oversight and Investigations, comes as the nation’s power grid grows increasingly vulnerable to cyberattacks, while incidents such as physical attacks and vandalism increased some 77% in 2022, according to the committee.

China is “almost certainly capable” of launching cyberattacks that would disrupt critical infrastructure services within the US, including oil and gas pipelines and rail systems, according to a report published earlier this year by the Office of the Director of National Intelligence.

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The hearing comes amid increasing tensions with China, including reports last week that Chinese hackers breached email accounts of US officials from the State Department, as well as US Commerce Department Secretary Gina Raimondo.

“Imagine what is possible if the CCP attacks our grid,” said Representative Cathy McMorris Rodgers, a Washington Republican who chairs the full committee.