Marin County officials will suspend indoor dining for at least three weeks amid an influx in new coronavirus infections, reversing course one week after giving restaurants the green light to serve customers inside.

The decision, effective at midnight Monday, comes days after the state added Marin County to its watch list, which closely tracks counties struggling to clamp down on a surge in cases and hospitalizations. The county’s decision was based on a lack of improvement in case counts, officials said in a release Sunday.

Marin had 2,861 total coronavirus cases and 21 deaths as of Sunday afternoon. There were 29,174 cases and 601 deaths across the Bay Area.

Gov. Gavin Newsom has directed counties on the watch list to reimpose parts of their stay-at-home orders.

The governor last week ordered 19 counties with surging coronavirus outbreaks — including Contra Costa, Santa Clara and Solano — to close indoor restaurants, wineries, movie theaters and other venues, saying California must keep the pandemic from spiraling out of control.

Twenty-two counties remained on the list as of Saturday.

Restaurants in Marin County may continue outdoor seating and take-out service, officials said.

Teams with the state health department will patrol restaurants and other businesses that are not complying with COVID-19 measures.

“Wearing facial coverings in public, washing hands often, adhering to social bubble guidelines, and practicing social distancing are among practices that will help curtail the coronavirus outbreak and lead to more openings in economic sectors,” Marin officials said.