Anne Arundel County, Maryland, has confirmed that hackers stole files from its networks during an incident in August. A county spokesperson told Recorded Future News that officials spotted "irregular activity" on August 28 and launched an investigation on a "limited subset of systems within the county computer network." That probe determined that an unauthorized actor gained access to a limited number of systems and copied certain files.
The county has not said what data was taken, noting that investigators are reviewing the files to decide whether any stolen information relates to county residents. Officials said they notified federal law enforcement and other government agencies. The breach was claimed by the Rhysida ransomware gang, which threatened to leak 2.6 terabytes of documents unless a $2 million ransom was paid. Rhysida has previously targeted governments in Kuwait, Seattle, Columbus, Ohio, and Berlin.
County officials described the August attack as a "separate incident" from a ransomware attack last year that forced the government to shut down multiple systems. Anne Arundel County announced on Thursday that it plans to send breach notification letters about that earlier incident on October 19. A spokesperson also pointed to a recent surge in "calculated cybercrimes" targeting state and local governments, citing outages in New Mexico, Utah, Texas, Nebraska, Missouri, and Arizona over the past two weeks.