Dalian, Liaoning province, reported 20 new locally transmitted confirmed COVID-19 cases and 12 asymptomatic carriers on Sunday, the provincial health commission of Liaoning announced on Monday.

In the latest resurgence of the virus, the northeastern province now has 40 locally transmitted confirmed cases and 28 infections with no symptoms — all in port city Dalian.

The first case was reported on Nov 4 in Zhuanghe city, administered by Dalian. Among the 20 cases whose information has been released, 14 are employees of a cold storage company in Zhuanghe.

Three village-level residential compounds in Zhuanghe have been raised to medium-risk level for COVID-19 control and prevention as of Sunday.

Zhuanghe's headquarters for COVID-19 prevention and control sent an open letter to all residents on Sunday. It thanked them for staying at home for the past several days and asked them to continue to stay at home and not go out.

Epidemic prevention and control practices have repeatedly proved at this stage, staying at home is the most effective way to stop the spread of the virus, and whether the city can win the battle against the epidemic as soon as possible is also depending on it, the letter wrote.

Dalian's headquarters for COVID-19 prevention and control announced on Sunday health control measures should be strengthened for those who visited Zhuanghe since Oct 14.

They should take a nucleic acid test immediately and report to their residential communities.

Those who visited medium-risk areas should have a 14-day quarantine for medical observation.

The headquarters released another notification on Sunday, requiring people in Dalian not to leave the city if not necessary in order to protect the lives and health of the general public and limit the spread of the epidemic.

Those who really need to leave the city must hold a certificate for a negative result of a nucleic acid test taken within 24 hours. They also should report to their residential communities and working units.

Since Sunday afternoon, residential communities in Dalian are arranging free nucleic acid tests for local residents.?

A notification from the city's education bureau said students of primary and secondary schools (including vocational schools and kindergartens) in the city should study online at home for two days, Monday and Tuesday.?

Because of the predicted snow, rain, ice, wind and strong decrease in temperature, districts and schools should arrange teachers to work at home and teach online.