HAYWARD, Calif. (KGO) -- The City of Hayward says was hacked. But officials say, so far people's private data is safe.
"There has been no evidence of which we are aware of any data breach, whatsoever," says Chuck Finnie, Communications and Marketing Officer for the City of Hayward. "The nature of this cyber-security event is a ransomware attack."
Finnie says this was a ransomware attack but didn't name who is behind it or what's being demanded.
VIDEO: City of Hayward's website down due to believed cyber-security attack, officials say
He says the problem was detected Sunday morning, and that city has since closed access to its public website and online portals.
Until the website is back online, the public can conduct business with the city by telephone, mail or in person.
"There is a forensic analysis going about how it happened and how to address it in the future," explains Finnie.
This comes after a recent ransomware attack in Oakland, in which, city officials say personal data was leaked.
Professor Ahmed Banafa at San Jose State University, says U.S. cities and organizations like hospitals and schools have been vulnerable in recent years.
"The last five years, we had 330 attacks that cost $70 billion dollars of downtime," says Banafa.
Cities like Hayward are what he calls "soft targets," meaning hackers believe they have weak IT defenses.
He recommends anyone who has conducted online transactions with Hayward to monitor their bank accounts and credit cards.
"Any kind of means that I used to communicate or pay the City of Hayward, I would be monitoring that very well," he says.
"I think it's very problematic what we are seeing, and it's only going to increase if we don't do something about it," says California State Senator Aisha Wahab, a former Hayward City Council member, who now represents parts of the East Bay.
Wahab, who has a background in tech, is praising the city's response, adding that the city made strides in recent years to beef up its IT systems. She says the big challenge for cash-strapped cities is cost.
"Tech services are extremely expensive," says Wahab. "And being able to prove and quantify that we are paying and investing in a contract that helps us with cyber security, it is very hard to kind of say if the dollars are worth it because you are never attacked regularly."
Wahab says Silicon Valley needs to offer discounts, and their services, to help cities deal with cyber security concerns. And also, that state agencies need to do more.
"The Office of Emergency Services for the State of California needs to step up and really have a game plan and some strategy around it. We are the fourth largest economy (in the world). And it's incredibly imperative that we protect our resources," says Wahab.
The city is still conducting business in person and over the phone. But Finnie says it could be weeks before they are back on track.
Although the city's website remains down, Hayward's 911 emergency dispatching, police, firefighter and emergency-medical services are still working.
The public can contact and conduct business with the city by telephone, mail or in person.
The city says if any data breach involving personal data is discovered, it will contact the affected individual or individuals directly.
City offices are open 8 a.m. to 5 p.m. Monday through Friday. The main Hayward City Hall phone number is (510) 583-4000.
The Hayward Public Library's hours are Monday-Wednesday 10 a.m. to 7 p.m., Thursday 11 a.m. to 6 p.m., and Friday and Saturday 10 a.m. to 5 p.m. Access to computers for public use will be unavailable until further notice.
Bay City News contributed this report
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