Six San Francisco Bay Area counties were expected to order a 3-week "shelter in place" starting on Tuesday, the San Francisco Chronicle reported on Monday.

The order, seen by the Chronicle, would close all but essential businesses and direct some 6.7 million people living in San Francisco, Santa Clara, San Mateo, Marin, Contra Costa and Alameda counties to not leave their homes as much as possible.

"Effective at midnight, San Francisco will require people to stay home except for essential needs," San Francisco Mayor London Breed said on Twitter. "Necessary government functions & essential stores will remain open."

The broader order reported by the Chronicle would make exceptions, including allowing people to shop for essential items and access healthcare, the Chronicle reported.

"One proven way to slow the transmission is to limit interactions among people to the greatest extent practicable," the order states, according to the Chronicle. 

Reuters