Los Angeles Mayor Eric Garcetti on Thursday issued a "Safer at Home" order, asking residents to stay home and limit all "non essential activities."
"I'm issuing a Safer at Home emergency order — ordering all residents of @LACity to stay inside their homes and immediately limit all nonessential movement. We're taking this urgent action to limit the spread of COVID-19 and save lives," Garcetti said in a tweet.
"Safer at Home" emergency order means all Los Angeles residents must stay inside their homes. The order will take effect from 11.59 p.m. PT on Thursday and continue until April 19. Workers of "impacted businesses" have an additional 24 hours, he said.
Residents can venture outside to buy groceries, or to the pharmacy to pick up medications. They can also take a walk or walk their pets, but keep at least six feet away from others.
They should not go to work unless they are providing essential services as defined by the order, or visit friends and family. They also should not travel for a job or a vacation outside the city. The order is mandatory, and not guidance, it said.
San Francisco Bay area officials on Monday became the first in the country to issue a "shelter in place" order that will affect nearly 7 million residents of six counties in the Bay Area as the region tries to contain the COVID-19 outbreak.
The order asks all residents of six Bay Area counties, including San Francisco, Santa Clara, San Mateo, Marin, Contra Costa and Alameda, to remain home as much as possible.
California estimates that more than half of the state — 25.5 million people — will get the new coronavirus over the next eight weeks, according to a letter sent by Gov. Gavin Newsom to U.S. President Donald Trump.
"In the last 24 hours, we had 126 new COVID-19 cases, a 21 percent increase. In some parts of our state, our case rate is doubling every four days," Newsom wrote in a letter dated Wednesday. Newsom asked Trump to dispatch the USNS Mercy Hospital Ship to the Port of Los Angeles through Sept. 1 to help with the influx of expected cases.
California reported nearly 699 confirmed cases as of 9 p.m. ET Wednesday night, according to the California health department. Newsom said the virus is spreading in the community in 23 counties across the state. It is the third hardest hit state in the U.S., behind Washington state which has 1,376 cases as of 6 p.m. EDT Thursday and New York which has at least 5,000 cases.
Earlier this week, Newsom ordered all non-essential businesses to close, including bars, beer pubs and wineries. Grocery stores, pharmacies, banks, cannabis clubs and other businesses deemed as essential are still open, state and local officials say.
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—CNBC's Dawn Kopecki and William Feuer contributed to this report.
This article has been updated to reflect that the order will take effect till April 19.