Chinese hackers are all but certain to disrupt American critical infrastructure, such as pipelines and railways, in the event of a conflict with the United States, a senior US cybersecurity official said Monday.

In comments made during an appearance at the Aspen Institute in Washington, Cybersecurity and Infrastructure Security Agency Director Jen Easterly said Beijing was making major investments in the capability to sabotage US infrastructure.

“This, I think, is the real threat that we need to be prepared for, and to focus on, and to build resilience against,” she told her audience.

She cautioned that Americans needed to be prepared for the likelihood that Beijing’s hackers would dodge their defenses and cause damage in the physical world.

“Given the formidable nature of the threat from Chinese state actors, given the size of their capability, given how much resources and effort they’re putting into it, it’s going to be very, very difficult for us to prevent disruptions from happening,” she said.

The Chinese Embassy in Washington did not immediately respond to a request seeking a reaction to the warning.

Easterly’s comments followed a question about an alleged Chinese hacking group known as Volt Typhoon, which US officials and cybersecurity companies accused of positioning itself to carry out destructive cyberattacks in the event of a conflict. Her comments expanded on a warning issued earlier this year by the US intelligence community, which said in its annual threat assessment that Beijing “certainly would consider undertaking aggressive cyber operations against US homeland critical infrastructure” and military targets should Chinese decisionmakers believe a major fight with the United States were imminent.

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