May 12 (UPI) -- A "ransomware" cyberattack targeted Britain's national healthcare system on Friday, affecting more than a dozen offices in a strike that hit a number of groups across industries, authorities said.
The British National Health Service said the "major" malware attack impacted 16 of its organizations, and hospitals and clinics in London and northwest and central Britain.
Authorities are still trying to determine exactly how many systems have been corrupted by the interference and identify the perpetrators.
Ransomware results from a sophisticated malware tool that can root into computer systems undetected and lock up important data. The perpetrators then offer to release the computer files for a price. In the NHS' case, the attackers sought $300 in online currency, or bitcoins, worth about $527,000.
"We believe the malware variant is Wanna Decryptor," NHS Digital said in a statement, adding that it's working with the National Cyber Security Centre, National Cyber Crime Unit and Department of Health "to support affected organizations and to recommend appropriate mitigations."
NHS officials said the cyberattack was not specifically aimed at the NHS, and that other groups across a range of industries were also targeted.
British officials advised people with non-emergency conditions to stay away from medical facilities that have been hit by the attack.
Ransomware attacks have spread globally in recent years after initially being used in Russia, experts say. Two years ago, the FBI estimated that one particular ransomware vehicle had taken more than $18 million.
Friday's strike showed the potential for cyber sneak attacks to create far-reaching consequences in countries like Britain, which has a single-payer, socialized healthcare structure.