Patients at a San Diego medical center have been warned that a hacker breached the center's computers and gained access to patients' personal information.

The University of California, San Diego's Moores Cancer Center sent a letter to 30,000 patients after the records were accessed late last month.

Spokeswoman DeAnn Marshall said the computer servers have information such as patients' names, birth dates and diagnosis and treatment dates. She says most patient information did not include Social Security numbers and there is no evidence any of the information has been viewed.


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The hospital says patients' medical records are stored in separate servers and were not breached.

Marshall says authorities are investigating.