The Chinese capital Beijing on Thursday closed some public places and ramped up testing in others as most of the city’s 22 million residents began more mass COVID-19 testing to avoid shutting down Shanghai-style.

Since Beijing started three rounds of mass screening this week in various regions, many residential complexes, administrative buildings and universities have been closed following the discovery of infections. Several schools, entertainment venues and tourist destinations were also closed.

Universal Studios in Beijing announced Wednesday night that visitors will be required to show negative test results before entering a theme park starting Friday.

In Beijing, positive cases of nearly 20 million samples were reported in the first round of mass testing, but the number remained low. The city recorded 56 new infections today, Thursday, up from 46 the day before.

As of April 22, Beijing has reported more than 160 cases, more than half of which have been in Chaoyang, the city’s most populous area known for its nightlife, shopping malls and embassies.

Although the number of infections is low, Beijing has remained in a state of expectation.

When the outbreak began in Shanghai, new infections were fewer than 100 a day from March 1 to 10, before reaching more than 700 on March 20.

By the end of the month, Shanghai had detected thousands of new infections, causing the city to close and the loss of its 25 million inhabitants.

Until now, Beijing has allowed residents to work even when tests are being carried out, unless infections are detected and a local lockdown is not mandatory.