US authorities are investigating cyberattacks targeting more than 30 water systems in Minnesota. While no major disruption to water supplies has been reported, officials are examining possible links to Iranian hackers following recent federal warnings about threats to critical infrastructure
Updated On – 31 July 2026, 11:30 AM
Washington: Authorities were working to find the source of cyberattacks that targeted more than 30 water systems in Minnesota and came amid warnings that Iranian hackers have been focusing on such systems.
Minnesota IT Services on Thursday said state officials had yet to identify who was behind the attacks that took place on Sunday and Monday. There were no reports that residents had been affected by the attacks, though one city asked residents to conserve water for a couple of hours while officials tried to determine what was wrong.
The FBI, which is investigating the attacks, has not publicly identified a culprit, and a spokesperson declined to say on Thursday who the bureau believed might be responsible. The FBI, Cybersecurity and Infrastructure Security Agency, 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.
Digital warfare has become an integral part of military conflict, and local water plants and healthcare facilities often lack the funds and expertise to install the latest software patches or take other security measures. That has made them a favourite target, both because of the relative ease of penetrating them and because of the panic such disruptions can cause.
Iran has the “geopolitical motivations” and a recent history of targeting water systems, said Cynthia Kaiser, the former deputy assistant director of the FBI’s cyber division, who has been closely monitoring threats to critical infrastructure from hackers linked to the country.
“I think most credible researchers and responders would be right to treat it like it’s Iran until proven otherwise,” added Kaiser, who is now the senior vice president of Halcyon’s Ransomware Research Center. “When it walks like a duck and talks like a duck, it’s really important to call it out.”
Iran’s interest in the operations of water systems inside the US dates back years. In 2016, the Justice Department charged a group of Iranian hackers in connection with a cyberattack targeting a small dam near New York City.
Minnesota IT Services said that as of Thursday, there were no active requests from Minnesota communities asking residents to modify their drinking water usage. The state agency said most of the confirmed attacks involved technology that water systems use to remotely monitor and control equipment. It said that being impacted meant investigators had confirmed malicious activity involving the system’s technology and did not mean every affected community had its water service disrupted.
The state agency said there were similarities among the incidents, including the timing and the types of technology used, but investigators had not determined whether the same culprit was behind each one.
For a few hours on Monday, the city of Braham asked residents to minimise water use as officials tried to determine why the water plant was offline. The city of about 1,700 people, located about 70 miles (113 kilometres) north of Minneapolis, said in a news release that the water plant outage was due to a cyberattack, but it did not cause any issue with water quality.
The city said the attackers shut down the operating controls, which shut down the well and water treatment plant. That left the city able to provide residents only with the water stored in the water tower for some time.
In Plymouth, a city of about 80,000 located outside Minneapolis, officials said on social media that their water infrastructure communications had been restored by Tuesday afternoon following a cyberattack. The city said crews were able to continue operating the system during the outage, and it did not have any impact on water levels or quality.
