Peninsula City Suspends Services After Ransomware Attack

Foster City takes computer systems offline as it investigates cybersecurity breach.

Mar. 21, 2026 at 12:08am

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The city of Foster City, California has suspended most non-emergency services after a ransomware attack hit its computer networks on Thursday. The city has declared a state of emergency and is working with cybersecurity experts to investigate the breach and restore its systems.

Why it matters

Ransomware attacks on local governments have become increasingly common, disrupting critical public services and exposing sensitive resident data. This incident highlights the vulnerability of municipal IT infrastructure and the need for robust cybersecurity measures to protect against such attacks.

The details

Foster City said its IT staff identified ransomware on the city's networks on Thursday, prompting officials to take most public services offline except for emergency response. The city manager's office has declared a state of emergency, which will allow Foster City to seek additional financial support. The police department's business phone lines were temporarily down but emergency lines remained operational. The city is now working with cybersecurity specialists to investigate the breach and restore its systems, while also warning residents to change passwords and protect personal data that may have been accessed.

  • The ransomware attack occurred on Thursday, March 20, 2026.
  • As of Friday, March 21 at 1 p.m., the city's services remained suspended.

The players

Foster City

A city located on the San Francisco Peninsula in California.

Stefan Chatwin

The city manager of Foster City.

Foster City Police Department

The local law enforcement agency for the city of Foster City.

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What they’re saying

“The public's safety is our highest priority, so we encourage members of our community to take precautions that would best assure the security of their personal information.”

— Stefan Chatwin, City Manager

What’s next

The city is working with cybersecurity experts to investigate the breach and restore its systems. The judge will decide on Tuesday whether to declare a state of emergency, which would allow Foster City to seek additional financial support.

The takeaway

This ransomware attack on Foster City's municipal infrastructure underscores the growing threat of cybercrime targeting local governments. It highlights the need for robust cybersecurity measures and emergency preparedness plans to protect critical public services and resident data.