Cyberattacks hit water systems in at least 12 US states

Cyberattacks targeting water and wastewater utilities have now been reported in at least 12 US states, up from seven just a week earlier, multiple sources told ABC News. Iran is the prime suspect, though officials have not confirmed its involvement.

The attacks can confuse utility managers by changing passwords and disabling alarm systems, according to people who have knowledge about the investigation. However, despite the quick spread from seven states to twelve, there have been no major interruptions to the water supply or sewage treatment facilities yet.

Is Iran behind US water system cyberattacks?

Officials have named Iran as the leading suspect but stopped short of formal confirmation. Investigators are reportedly also examining whether the actor behind the attacks deliberately mimicked known Iranian tactics to escalate tensions rather than acting on Tehran's behalf.

President Trump said on Friday he does not "think there was an Iranian cyberattack", a comment that runs against assessments circulating among some federal officials.

The FBI is advising affected utilities to disconnect systems from the internet wherever possible, install physical breakers, and ensure staff are prepared to revert to manual controls if automated systems are compromised.

The guidance echoes warnings issued after a cluster of earlier attacks on Minnesota's water systems, which investigators have linked to a similar pattern of tampering.

Michigan is one of the states caught up in the intrusions. State police say they are monitoring the situation and coordinating with federal partners, working alongside the state's Department of Environment, Great Lakes, and Energy to alert municipal water systems and encourage operators to secure affected software.

Officials there said all systems continued operating safely, with no known impact on public health, and referred further questions to the FBI, which is leading the investigation.