The City of Newburgh remains offline Thursday for the third day after what county officials say was a serious cybersecurity attack that’s holding city data at ransom. City officials announced the hack Tuesday morning.

They say their police and fire emergency operations have not been affected but that state and county officials say they have had to provide emergency help to the city's police department because of the disruption.

The city says it can’t accept payments because of the breach and that two of their buildings are closed to the public until further notice. News 12 spoke to an information technology expert who says it can take a week or more for the city to get back online and that oftentimes, hackers threaten to release personal information to the public.

“Exfiltration of the data is the worst thing that could happen. That’s where the ransom comes in,” says Long Island-based tech solution provider Adam Schwam. “They are going to say, we have your data, here’s a snippet of it. How much are you going to pay us not to release it?

County officials say the FBI is investigating and believes the City of Newburgh was hit by a “known group” in a “targeted” cybersecurity attack.

Schwam says it could cost the City of Newburgh more than $500,000 to recover from the breach.

“At the end of the day, this is a war. The war is not fought by planes anymore. It’s fought by hurting our economy and that’s what they’re doing," says Schwam.