Health care and medical services were briefly shut down Wednesday in rural Oregon.
The state is investigating a cyberattack that affected more than 300,000 Oregonians and impacted the health system.
The federal Centers for Disease Control and Prevention has also been notified.
The Department of Health and Human Services said it will conduct an investigation and said the state is cooperating with the federal investigation.
A spokesman for the Oregon Health Authority said the shutdown was caused by a data breach.
The affected states were: Oregon, Washington, Idaho, Montana, Arizona, Montana and California.
The Health Department and state officials said that some of the affected areas have reopened, but many others are not.
The Oregon Health and Science University is the state agency responsible for health services in the state.
Health care services were disrupted when the data breach occurred, according to a statement from the Oregon Department of Public Health.
“It is important to note that we are working to restore access to health care services as quickly as possible,” the statement said.
It said Oregon Health, the state’s largest health insurer, was “working with state agencies and others” to restore services.
The Centers for Diseases Control and Protection and the U.S. Department of Agriculture said that the outbreak could be traced to the “distributed denial-of-service attack” against the health insurance website Anthem.
Anthem is a unit of UnitedHealth Group.
The website for Anthem has been up since March.
In a statement, the company said it was working with health care providers to resolve the situation.
“We have been in contact with Oregon health officials, and have a number of resources available to help in this effort,” the company added.
“Our commitment to providing safe, quality healthcare services to all Oregonians remains unchanged.”
Anthem said it would offer free care to anyone who wanted to seek care.
“At Anthem, we value our partnership with Oregon Health.
This is our second attack against Anthem, and we will continue to take all necessary actions to ensure the health and safety of all Oregonian consumers,” Anthem said in a statement.
The Anthem breach has affected nearly 7,000 health insurance customers and affected tens of thousands more.