Beijing health officials reported a local confirmed case of COVID-19 on Wednesday afternoon at a news conference. The case was found during community testing in Haidian district.

The infected person, who had mild symptoms, had returned to the capital by train on Sunday and went to work on Monday, visiting public places, including restaurants and a swimming pool, said Liu Xiaofeng, deputy director of the Beijing Center for Disease Prevention and Control.

The person had also taken subways and used shared bicycles, Liu added.

The person was quarantined at a centralized center on Tuesday after close contact with a confirmed case outside Beijing. A nucleic acid test came back positive on Wednesday and was subsequently confirmed.

According to Lin Hang, deputy head of Haidian district, the district has designated four high-risk areas, all of which the infected person had visited.

Mass testing of residents and the environment in the places visited has been done. All results have come back negative, Lin said.

Liu noted that Beijing is facing increasing pressure in epidemic prevention and control. The city saw a spike as residents returned from holidays and students returned to school.

He added that people who returned to Beijing should not gather for meals or go to crowded places within seven days, since many places outside Beijing have experienced new rounds of COVID-19 outbreaks.

The city will also scale up screening and monitoring to cut off transmission chains in a timely manner.

Beijing also reported a confirmed case on Tuesday. It was discovered in a centralized quarantine center in Chaoyang district. That patient was also a returnee from outside Beijing and had returned by car on Saturday. The person was quarantined the next day because of close contact with a confirmed case outside Beijing. A positive test for the virus came back on Monday and was confirmed on Tuesday.

Beijing has reported 23 local positive cases since Aug 15, involving seven districts, Liu said.