The attackers may have taken information related to health-insurance coverage and certain medical information as well as the University Health Services (UHS) medical-record number, dates of visits or names of healthcare providers seen, as well as information such as Social Security Number, according to the statement released by UC Berkeley.

About 160,000 individuals are believed to be impacted, including about 3,400 Mills College students whose medical care is tied to health care at Berkeley. Social Security Numbers are used as unique identifiers for students enrolled in the campus Student Health Insurance Plans, the university says.

"The university deeply regrets exposing our students and the Mills community to potential identity theft," said Shelton Waggener, UC Berkeley"s associate vice chancellor for information technology and CIO, said in the statement.