An emergency communications system used by several small towns across northern Massachusetts was impacted by a cyberattack that began on Tuesday. 

The Patriot Regional Emergency Communications Center said the intrusion impacted town and public safety computer systems. While 9-1-1 phone systems still work, non-emergency and business phone lines are out of service. 

The center is used by the towns of Pepperell, Ashby, Dunstable, Groton and others as a regional hub for receiving emergency calls and dispatching police, fire or medical services. The center is based in Pepperell. 

Officials said Wednesday they are working with IT vendors to investigate the attack and recover from the incident. 

“We immediately engaged our insurance provider and reputable outside cybersecurity agencies to respond to and mitigate this attack,” said Pepperell Town Administrator Andrew MacLean. 

Pepperell’s government did not respond to requests for comment about the incident. Federal law enforcement have been notified of the attack. 

Cybersecurity experts are in the process of determining what information may have been accessed or stolen during the attack. 

The Pepperell Police and Fire departments are still responding to emergency calls and the town said other local police and fire departments “can still reach Patriot Regional Emergency Communications Center through normal mutual aid channels.”

The town website says the system is linked to CodeRED — an emergency notification service that allows municipal leaders to notify local residents of emergency situations, weather changes, updates on disasters, AMBER alerts, evacuation orders and more.

The CodeRED system faced its own cyberattack in November when a ransomware gang targeted parent company Crisis24. That incident took down the CodeRED system in dozens of municipalities across the U.S. 

Crisis24 told Recorded Future News at the time that the hackers not only damaged the CodeRED environment but also stole information on the local officials who controlled their municipalities’ CodeRED system. 

The company urged users who reused their CodeRED password for any other personal or business accounts to change those passwords immediately.

Several municipalities in Massachusetts warned local government officials at the time to change the passwords they used for the CodeRED platform. 

Ransomware gangs have previously targeted a prominent ambulance service in Milwaukee and other emergency services in municipalities across the U.S.