The port city of Dalian, Liaoning province, has announced restrictive measures including a work at home order and calls to avoid unnecessary trips from Tuesday to Saturday to curb the spread of the latest resurgence of the virus, the city's COVID-19 prevention and control headquarters said on Monday.

In downtown regions like Zhangshan district and the High-tech Zone, residents are required to stay home to avoid unnecessary trips and advised to work at home except those working to ensure the city's operation, according to a notification released on Monday evening.

People are required not to leave the city. Those who have to leave must report to their neighborhood and employers and hold a certificate for a negative result of a nucleic acid test taken within 48 hours.

During this period, public transportation in the main urban area such as buses and subways will be suspended, while taxis and online ride-hailing services will continue to operate.

Museums, theaters, gyms and other indoor public places will be closed. Dining at restaurants is not allowed.

Students of primary and secondary schools (including vocational schools) in the city, who were scheduled to start the new semester on Sept 1, should suspend their return to school and implement online teaching.

Dalian reported 15 asymptomatic COVID-19 carriers on Sunday, all found from nucleic acid screening of key areas, the city's COVID-19 prevention and control headquarters said on Monday.

The gene sequencing results of the cases were highly homologous to the ones discovered in Dalian since Aug 20. Preliminary results showed the source was the accidental exposure of non-closed-loop management personnel in a centralized isolation hotel for international travelers, which resulted in infection and further transmission.