The City of Suisun remained closed at the start of the week as public safety workers continued their response to a cybersecurity incident that shut down City Hall.
Suisun city officials declared a state of emergency on Aug. 8 after malicious software infected and compromised IT systems on the morning of Aug. 7.
“To contain the threat and preserve evidence for a federal investigation, the City shut down its entire IT network,” officials said.
The source of the malicious software, how it entered the city's systems, and who may be responsible have not yet been announced.
The Northern California city is working alongside federal, state and regional agencies, including the FBI, Department of Homeland Security and California Office of Emergency Services to maintain emergency services, investigate the incident and restore systems.
“Suisun City police officers and firefighters will continue responding to calls for service,” officials said. “Many online systems and internal operations are temporarily unavailable as we work with cybersecurity experts to investigate and restore full functionality.”
Suisun City is located in Solano County, about 45 miles away from both San Francisco and Sacramento.
Although there is no imminent threat to public safety, the city activated its Emergency Operations Center.
On Monday, public safety services and response were active in Suisun City, however some services were limited or closed to the public.
For example, online city services and internal operations are still temporarily unavailable.
“The Police Department lobby is open and accessible for ticket sign-offs, vehicle releases, speaking with an officer and general assistance,” city officials said.
The lobby is open Monday through Thursday from 7 a.m. to 5 p.m., with possible closures for lunch from noon to 12:30 p.m.
Because City Hall is closed, in-person meetings with certain departments are suspended. Those departments include planning, building, housing, water, finance, human resources, public works, the city manager and administration.
The declaration of a state of emergency under Government Code 8630 allows the City to access emergency support services and to recover costs incurred as a result of the cybersecurity incident.
Municipal cyberattacks in Northern California have surged in recent years.
In March, Foster City experienced a ransomware attack, which forced non-emergency municipal services offline and prompted a local state of emergency declaration as well.