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LOS ANGELES — Residents of the city of Los Angeles will have to wear face coverings if they venture out to grocery stores, pharmacies or other essential businesses allowed to serve the public amid a statewide stay-at-home order.

"Every Angeleno will share this responsibility with employers: to keep workers and everybody else safe, which is why we are requiring customers to wear face coverings to enter those businesses," Mayor Eric Garcetti said Tuesday in issuing the facial covering mandate, which takes effect Friday.

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"If you're shopping for groceries, picking up a prescription or visiting any other essential business, and if you're not covering your face, by Friday morning an essential business can refuse you service," the mayor said.

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He said workers at those businesses would also have to wear face coverings. The order is designed to prevent the person-to-person spread of the coronavirus.

"These critical places where we do come into contact with each other — those workers also must wear a facial covering," Garcetti said.

Garcetti recommended last week that residents wear face coverings. A day later, the Centers for Disease Control and Prevention said the same for all Americans.

The mayor was also ahead of the curve on stay-at-home orders, announcing a Safer-at-Home program with Los Angeles County leaders on March 19.

County health officials said Tuesday that there have been 6,910 coronavirus cases and 169 deaths since the pandemic began.

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Garcetti said he's spoken to Los Angeles County supervisors who represent the county's 10 million residents and the leaders of nearby cities about making the mask mandate regionwide.

"Cover up, save a life. It's that simple," he said.