Real estate deals have ground to a halt following a cyberattack on the Suffolk County government earlier this month.

Verifying property titles and filing records has been impossible since the cyberattack more than 20 days ago, bringing all deals in the county to an abrupt stop, The Real Deal reports. County websites, servers and databases were shut down by a hack from a group known as BlackCat on Sep. 8, The Suffolk Times reported.

The hackers reportedly claimed to have downloaded more than 4 terabytes of data, including data belonging to individual residents, and have refused to restore access to the government servers until a ransom is paid. Online databases remain inaccessible, as do county email addresses, TRD reports.

While county officials have started to accept some records in person, the hack has already caused severe disruption for brokers, lawyers, buyers, sellers and title companies. Meanwhile, banks and buyers have no way to verify if properties are free of liens or if sellers are legitimate owners.

“Real estate transactions are on hold,” Ronkonkoma-based law firm Gulotta & Gulotta founding partner Michael Gulotta told TRD. “About 45% of our business is real estate. This has impacted our staff, clients and affiliates in a major way.”

But even for records delivered in person, the inability of officials to file records electronically during this period could lead to further complications. In New York State, the first person to file title claims on a property is the person whose claim is counted, meaning that people could lose property claims if documents are filed in the wrong order.

While some deals are closing, most have been put on hold — potentially leading to contracts falling through. Mortgage rates have increased around a full percentage over the past two weeks with Freddie Mac pegging the average 30-year mortgage at 6.7% as of Thursday.