Foreign hackers broke into a water plant control system in Illinois last week and damaged a water pump in what appears to be the first reported case of a malicious cyber attack damaging a critical computer system in the United States, according to an industry expert.

On Nov. 8, a municipal water district employee in Illinois noticed problems with the city’s water pump control system, and a technician determined the system had been remotely hacked into from a computer located in Russia, said Joe Weiss, an industry security expert who obtained a copy of an Illinois state fusion center report describing the incident.

“This is a big deal,” said Weiss. The report stated it is unknown how many other systems might be affected.

The Department of Homeland Security confirmed that a water plant in Springfield, Ill. had been damaged, but spokesman Peter Boogaard said officials had not yet determined that the water pump failure was caused by a cyber-attack. “DHS and the FBI are gathering facts surrounding the report of a water pump failure in Springfield, Illinois. At this time there is no credible corroborated data that indicates a risk to critical infrastructure entities or a threat to public safety,” he said.

Dave Marcus, director of security research for McAfee Labs, said that the computers that control critical systems in the United States are vulnerable to attacks that come through the Internet, and few operators of these systems know how to detect them. “So many are ill-prepared for cyber attacks,” Marcus said.

Senior U.S. officials have recently raised warnings about the risk of cyber attacks on critical infrastructure. Questions persist about the readiness and capabilities of DHS to respond to a major attack, and the scope of authority of the U.S. military, which has the greatest cyber operational capabilities, to respond.

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