"The recent cases in Beijing, as well as the sporadic infections across the country, are within expectations given the global spread of the virus."

Wu mentioned that Beijing would have become comparable to "Wuhan early this year" if the city had not rapidly taken strict measures to halt the spread in an accurate way after the first case was reported on June 11.

In addition to mass nucleic acid testing for all people who had been to Xinfadi or had contact with people linked to the market, schools in Beijing also are taking strict measures to curb the spread of the virus.

Dongcheng district is requiring all graduating students in junior and senior high schools to have a coronavirus test before they can take entrance exams for college or high school, both scheduled to take place next month.

Security inspection stations have been set up on the city's highway toll booths, giving departure permission only to those travelers with a recent negative nucleic acid test report, Pan Xuhong, deputy director of the municipal public security bureau, said on Thursday.

People with confirmed or suspected cases, close contacts and those with positive test results but no symptoms will not be allowed to buy airline or train tickets.

People who have traveled to Xinfadi wholesale market or who have had close contact with market workers since May 30, as well as the residents living in areas designated as medium-and high-risk, are also forbidden to leave Beijing.

"However, strengthening the management of high-risk groups by banning them from leaving the city doesn't mean there's a lockdown," Pan said. "Travelers with negative nucleic acid test results can leave the city after a temperature check."

Also, the National Development and Reform Commission has organized the delivery of 5,000 tons of vegetables from neighboring Hebei province to Beijing to help ensure the supply of daily necessities to residents of the city, according to Wang Hongcun, an official at the municipal commerce bureau.