Heilongjiang province on Sunday reported 27 new locally transmitted confirmed cases of COVID-19, according to the provincial health commission on Monday.
Among the confirmed cases, 25 were found in the city of Heihe.
The other two were found in its capital city Harbin and were related to the recent outbreak in Heihe.
The coronavirus risk levels of two residential communities in Pingfang district in Harbin were raised from low to medium starting from Monday, the city's epidemic prevention and control headquarters said on Sunday night.
Starting from Monday, all the kindergartens, primary schools, middle schools and vocational schools in Harbin will be suspended for one week, according to a government statement on Sunday.
Schools will provide online courses during the period, the statement said.
The Harbin epidemic prevention and control headquarters released a statement on Saturday suggesting people suspend unnecessary trips out of the city.
Residents who have to leave Harbin for special reasons should present a green health QR code and provide negative nucleic acid test results within 48 hours, the statement said.
Venues for the public such as educational institutions, entertainment facilities and private clinics are suspending their services.
Harbin also suspended all performances, competitions, forums, exhibitions and other large-scale activities until further notice.
Meanwhile, all scenic spots in the city will be allowed to receive visitors in up to 50 percent of their capacities.
All welfare, nursing and mental health institutions have been put under lockdown management.
Since the first case in the latest outbreak was reported in Heihe on Wednesday, Heilongjiang has reported 82 local confirmed cases, including 79 in Heihe and three in Harbin.