The FBI said the same group of cyber extortionists accused of attacking the Irish medical system last week also affected at least 16 networks of American medical and emergency personnel.
The Federal Bureau of Investigation (FBI) said that cybercriminals using malware called Conti have targeted law enforcement, emergency medical services, dispatch centers and municipalities.
The alert did not mention the victim, nor did it elaborate on the nature or severity of the infringement. Only they are one of more than 400 organizations worldwide targeted by Conti Actors.
The US Federal Bureau of Investigation (FBI) did not immediately return a message seeking more detailed information about the notification, which was first reported by IT security news website Bleeping Computer.
After the Conti-related attack, it shut down its network last Friday. The rescue raid paralysed diagnostic services, interrupted testing for COVID-19, and caused the hospital to abandon appointments.
Irish Minister Ossian Smyth, responsible for e-government affairs, said that this may be the most important cybercrime attacking Ireland.
The Irish government stated that it has not paid and will not pay any ransom in exchange for the so-called keys. The hacker has not yet responded to Reuters seeking comment.