The parent company of Illinois American Water is pausing billing after its computer systems were breached by hackers last week.
American Water said in a filing with the U.S. Securities and Exchange Commission on Monday that unauthorized activity was discovered in its network and computer systems on Oct. 3.
The exact nature or origins of that incident weren't immediately known. The company said it's working with third-party cybersecurity experts and law enforcement.
The company said it is disconnecting or deactivating certain systems to protect data. That includes the MyWater payment system.
"There will be no late charges or services shut off while MyWater remains unavailable. Additionally, our call center has limited functionality while MyWater is offline. We are working diligently to bring these services back online safely and securely," the company said in an FAQ on its website.
The filing indicates American Water doesn't believe any water or wastewater facilities are negatively affected, but the full impact isn't yet known. The company said water remains safe to drink. The company is investigating whether customer information was compromised.
Foreign cyberattacks on U.S. water utilities are becoming a bigger concern. Government officials warn that hackers in Iran and China are among those actively targeting critical infrastructure like water treatment plants.
Illinois American Water, which provides service to Peoria, Pekin, and other Central Illinois communities, is one of the nation's largest private water and wastewater providers, serving more than 14 million people in 14 states.