MedStar Health has announced that it has shut down its electronic medical record system after confirming that it has been struck with malware.

MedStar indicated that it doesn’t yet know whether the virus is ransomware similar to other recent attacks against health care entities, but that no protected health information has been compromised. MedStar, which consists of 10 hospitals in the Washington, D.C. area, is staying open and using paper health records.