SAN FRANCISCO (KCBS)— San Francisco city officials are warning residents of a scam, where would-be burglars are posing as water department workers. Clad in bright vests and hard hats, the fake workers have been knocking on doors, claiming to work for the department, according to police.

Officials along with San Francisco Police Department held a news conference this week where they provided details of a December 18th residential burglary on the 1700 block of 19th Avenue where three individuals posing as SF Public Utilities Commission water department workers gained access to a house.

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“They did have a considerable loss of valuables and also monetary cash loss,” said Police Capt. Theresa Barrett. She added the suspects had orange vests on but no I.D. Police do however have video of the suspects and it is an active case.

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Police warned that wearing a hard hat and a vest doesn’t ensure that a person is a city employee. Residents have been asked to keep an eye on elderly neighbors, who may be vulnerable to such scams.

Assistant General Manager of San Francisco Water Enterprise Steve Richie said virtually all water department work takes place on the street or the sidewalk, and water employees will not enter a home without an appointment.

“Water department employees are always identified by an official ID badge. You can see I’ve got mine here,” he said.

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The real workers also drive city vehicles— white with the city seal and an I.D. number.