Facing a sharp increase in coronavirus cases in Beijing, China has cancelled more than 1,200 flights in and out of its capital on Wednesday, the New York Post reported.

This accounts for about two-thirds of all incoming and outgoing flights from Beijing.

After two months of no new instances of coronavirus, the number of confirmed cases in the capital has increased to 137 within the last week.

China shut down a total of 11 markets in the city and all schools, as well as banning those living in “medium- or high risk” areas of Beijing from leaving.

“The risk of the outbreak spreading is huge and controlling it is difficult,” Pang Xinghuo, a senior disease control official, told a press conference. “[We] can’t rule out the possibility the number of cases will persist for a period of time.”

The food market that is the apparent source of this latest outbreak has had more than 200,000 visitors since May 30 and is significantly larger than the one in Wuhan, where the coronavirus was first detected.

The flare-up in Beijing is the worst resurgence of coronavirus in China since the initial pandemic was, for the most part, brought under control in March, CNN reported.

In additional attempts to contain the spread, an increasing number of cities and provinces in China have said they will place restrictions, such as mandatory quarantine, on anyone arriving from Beijing.

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