Transcript for Mass hack simulation for medical, security, and government personnel in Phoenix
Next, the global cyberattack revealing a threat to Americans. The ransomware attack in the U.S. Hospitals, putting lives at risk. Dan Harris reports that hospitals and medical systems may not be ready for another attack. Reporter: The ransomware virus known as "Petya" has taken out computer systems all over the planet, including those at hospitals near Pittsburgh. She called me and said surgery was canceled because the computers were down. We need an ekg right away and a chest x-ray. Reporter: Experts say it should be a wake-up call for the American health care system. Sir, let's start cpr. Reporter: Doctor ruha has no idea what everyone around them in this simulated E.R. Knows, that this patient is the victim of a hack. ABC news was right there recently when medical professionals, security experts, and government employees came to Phoenix to witness the first ever simulated mass hack of a hospital. So you had no idea this was a hack? I knew there was a problem with the aicd, but I had no idea it was hacked. Reporter: The goal of this exercise, to bring awareness to a fax recently highlighted in a congressional report, which said the security of our healthcare systems is in "Critical condition." With so many medical devices connected to the internet, they are now considered potential threats. Dan Harris, ABC news, Phoenix, Arizona. You can see that full report on "Nightline."
This transcript has been automatically generated and may not be 100% accurate.