About 13,000 California home healthcare workers had their Social Security numbers exposed online for nine days after being mistakenly posted on a website for Medi-Cal, KCRA-TV reported on Tuesday.

The California Department of Health Care Services (DHS) confirmed that the leak happened last month, the second security problem involving health care workers in the past five months, before the information was removed from public view.

"They did it again," said one worker, Julie Hensen. "It's really gonna hurt a lot of people. The bad guys are gonna be out there in seventh heaven."

Another security breach earlier this year led to the names and Social Security numbers of 750,000 home-care workers and clients being compromised when an unencrypted microfiche tape containing payroll data went missing. A subsequent investigation determined that the information, shipped via mail, had been destroyed by the U.S. Postal Service.

A DHS spokesperson said the state will institute "extra procedures" to avoid more breaches in the future, and has offered free credit monitoring services for workers concerned about falling victim to identity theft.

Watch KCRA's report on the latest security breach, aired Tuesday, below.

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