Community water systems in 30 Minnesota towns and cities were hit this week by a "coordinated cyberattack," state officials say.

Minnesota IT Services (MNIT) said in a statement that it had activated the state's cybersecurity incident response capabilities, while it coordinates with federal, state, tribal and public-sector partners to investigate the attack. 

"Cyberattacks against critical infrastructure require a coordinated, whole-of-government response," said John Israel, MNIT Assistant Commissioner and Minnesota Chief Information Security Officer.

The investigation remains active, the agency said, and the state is still assessing affected systems. The agency added that it wasn't aware of any notices asking residents of the communities to modify their drinking water usage.