Beijing has set about testing hundreds of thousands of people for the novel coronavirus in an exhaustive effort to stamp out a new eruption of the disease in the Chinese capital.

After dozens of cases were reported over the weekend, continuing into Monday, Chinese authorities mobilized almost 100,000 community workers to test everyone who has worked in or visited the Xinfadi market in the southwest of Beijing.

Xinfadi is the largest fruit, vegetable and meat market in the capital, which is home to about 21 million people, and supplies 70 percent of the city’s fresh vegetables and 80 percent of its fruit.

But after discovering more than 90 new infections linked to the market over the weekend, and 36 more being reported Monday, Beijing’s health authorities are taking military-style action to try to ensure the virus doesn’t spread further.

“These clustered cases are highly correlated with the Xinfadi agricultural wholesale market, which has a highly mobile crowd and poses great outbreak risks,” Vice Premier Sun Chunlan said at a State Council briefing, according to state media reports Monday. “We have to take firm action and resolute measures to effectively stop the epidemic from spreading,” she said.

The sudden appearance of scores of infections, both symptomatic and asymptomatic, highlights the resilience of the virus and its rapid spread despite tight social controls. It also underscores the dangers of markets as the virus is believed to have originated in the Huanan food market in the city of Wuhan before it spread worldwide.

More than 77,000 people were tested Sunday and 200,000 were expected to be tested Monday, Beijing municipal authorities said.

Everyone who has visited the market since May 30 is ordered to isolate themselves at home, and residential compounds around Xinfadi and another nearby market, Yuquan, have been sealed off so that residents can’t wander freely. Nine kindergartens and elementary schools around Xinfadi were also ordered to close.

The first signs that the cluster was linked to Xinfadi came with a man who tested positive after visiting the market on June 3 to buy meat and seafood. Then on Friday, the Chinese Center for Disease Control and Prevention announced that two quality-control workers who had been in the market checking standards had also tested positive.

Beijing authorities have quickly imposed strict controls across the capital, requiring students to again wear masks in their classrooms at school, ordering restaurants to cancel banquets, and telling gyms and movie theaters to close up.

Fresh salmon has been removed from markets and stores all over the city, and frozen and fresh meat everywhere will now be screened, authorities said.

After the start of the outbreak in Wuhan, top officials in China’s Communist Party tried to ensure that the virus did not rage in the politically sensitive capital.

But the surprise outbreak, months after the party had declared victory over the virus and held up its response as exemplary, is inconvenient for its leaders.

Key party officials were removed from their posts because of the outbreak, the Beijing Daily reported Monday. These included the party secretary in the area that incorporates Xinfadi and the general manager of the market, while the deputy head of the district was fired for “failing” in his duty to prevent and control the coronavirus.