The California Department of Public Health says the personal information of nearly 9,000 current and former employees has been breached. The information includes names and social security numbers.
The Department of Public Health says an employee copied the data files to a private hard drive and removed it from state offices.
The security breach affects nearly all current employees at the department as well as 3,000 former workers.
Beth Givens directs San Diego's non-profit Privacy Rights Clearinghouse.
"Gaining access to sensitive information within a workplace is not all that difficult," Givens said, "especially if the workplace doesn't have heavy duty, rigorous policy and procedures in place. And that appears to be the situation with the department."
The agency said it's doing a thorough review of security policies.
Givens said nationwide, more than 22 million personal records have been breached this year.