Michigan reports cyberattacks on nine water systems, with the FBI investigating

The US state of Michigan has reported cyberattacks on nine of its water systems, days after Minnesota reported similar breaches across 30 sites. The FBI said on Saturday 1 August 2026 that it is investigating both cases, and had said in an earlier advisory that at least seven states have reported incidents, though only Minnesota and Michigan have been identified so far.

No culprit has yet been pinpointed. The breaches came after the FBI, the Cybersecurity and Infrastructure Security Agency (CISA) and other agencies warned in an advisory last week that Iranian hackers have been targeting water and wastewater systems and the operational controls of other critical infrastructure sectors. Dale George, director of communications for Michigan's Department of Environment, Great Lakes and Energy, said all systems continued to operate safely following the attacks.

US President Donald Trump, responding to the Minnesota attacks, said he did not think there had been an Iranian cyberattack. Minnesota Governor Tim Walz said he believes Iran was behind it. Minnesota IT Services said most confirmed attacks involved technology that water systems use to remotely monitor and control equipment, and that as of Thursday there were no active requests for residents to modify their water usage.