American Water, the largest water and wastewater utility in the U.S., revealed on Monday that it suffered a cyberattack which has disrupted customers’ access to its billing and payment platform, MyWater. The company, which serves over 14 million people across 14 states and 18 U.S. military installations, detected “unauthorized activity” in its systems on October 3 and swiftly deactivated its payment portal to prevent further damage and secure customer data.

Despite the disruption to billing services, American Water assured its customers that water and wastewater operations are unaffected, and the water remains safe to drink. The company has implemented its incident response protocols, brought in third-party cybersecurity experts, and is working with law enforcement to address the situation. Customers will not face late fees or service disconnections during the outage, and the company is working to restore its systems safely and securely.