LOS ANGELES (CBS/AP) — California regulators say nearly 80 people face criminal charges for doing contracting work without a license following a broad-reaching undercover operation.

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The California Contractors State License Board said Friday the stings were conducted this week in Orange, Los Angeles, San Bernardino and other counties.

Investigators posed as homeowners seeking bids for home improvement projects like painting, electrical work and masonry. Most of those caught had posted Craigslist advertisements for their services.

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KCAL9’s Randy Paige reports that it is illegal for a contractor without a license to bid a job that costs more than $500 for materials and labor.

“Think of it like a doctor. Would you hire a doctor without a license,” Rick Lopes of the California Contractors State License Board said, adding that licensed contractors offer more protections for consumers.

“Not only do those people have to pass a criminal background check and exams to show that they are minimally competent to do the work, but there’s also protections in place should something go wrong,” he said.

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