Change Healthcare, a subsidiary of US health insurance giant UnitedHealth Group (UHG), was possibly breached by hackers backed by a government, according to a filing with government regulators.

Change Healthcare provides patient billing across the US healthcare system. According to the company, it performs billions of healthcare transactions annually and claims to manage the data of almost one-third of all US patients, or about 100 million people.

Change Healthcare Attacked by Government-Backed Hackers

According to TechCrunch, UHG cited on Thursday in the filing that nation-state hackers were the ones conducting the ongoing cybersecurity incident affecting Change Healthcare.

However, the firm did not specify which country or government it believed was behind the hack or provide any proof to support its assertion. It also did not have a timeline for when its systems would return online.

The event tracker for the organization indicates that the intrusion started early Wednesday. The precise details of the breach remain unknown at this time.

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US Pharmacies Affected by Change Healthcare Hacking Incident

Because of the ongoing outage at Change Healthcare, which processes most of the billing process, pharmacies nationwide said they cannot fulfill prescriptions through patients' insurance.

According to many sources who spoke with TechCrunch, the ongoing cyberattack was causing downtime for those working in the healthcare industry and whose work was affected by the outage.

UHG has informed its clients, customers, and certain government authorities of the incident. It also said it has hired top security specialists and is working with law enforcement.

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