SAN FRANCISCO (AP) — California authorities arrested 75 people, some with shady pasts and most of them accused of working without proper licenses, during an undercover sting operation conducted last week by the Contractors State License Board.

The board announced Friday that its annual operation netted two registered sex offenders, two people with multiple felony records and three with open warrants for their arrest.

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“Homeowners should be nervous when they hear the background of some of the people we caught in these stings,” said board registrar Steve Sands. “Unlicensed, illegal activity that puts homeowners at risk and legitimate contractors at a competitive disadvantage will not be tolerated.”

Some 72 of those arrested are suspected of operating without contractor’s license. They face a maximum sentence of six months in jail and a $5,000 fine if convicted.

The board said the majority of suspects were found through advertisements on The board also said 56 of the suspects may be charged with illegal advertising and 10 of them with requiring an excessive down payment.

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Anyone can advertise to perform jobs of less than $500, but ads must state they are not licensed contractors. Illegal advertising convictions fetch maximum fines of $1,000 each.

Meanwhile, a home improvement project down payment in California cannot exceed 10 percent of the contract total or $1,000, whichever is less. A conviction of requiring an excessive down payment carries a maximum penalty of six months in jail and a $5,000 fine.

Investigators of the annual autumn “California Blitz” posed as homeowners seeking bids for home improvements such as painting, electrical, plumbing, landscaping, flooring, drywall, fencing, concrete, and tree removal work.

Arrests were made in six California locations on Wednesday and Thursday, including in the area burned in the recent Silver Fire near Banning in Riverside County. The board said more arrests may be coming because some suspects are expected to provide fax or email bids to undercover agents at a later date.

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