GALT (CBS13) – A ransomware attack has knocked out several of the city of Galt’s digital communications platforms, say city officials.

In the early hours of December 16, hackers were able to put malware on the City of Galt’s computerized systems in order to take over those systems in exchange for money. The city says it doesn’t know how much the hackers want.

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The city’s email server was damaged in the attack, knocking out email communication to and from city accounts. The city’s telephone service was also affected, preventing people from being able to call the city offices. Police emergency 911 phone lines were not affected in the attack.

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Employees investigating the extent of the attack say it does not appear that personal data has been exposed.

The city is working with the California Department of Justice and the FBI to investigate the incident.

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Galt is just one of several public agencies hit with ransomware over the past few months, the city says.