DALIAN, Dec. 27 (Xinhua) -- Another 10 communities and villages were classified as medium-risk areas for COVID-19 in the northeastern Chinese city of Dalian, bringing the city's total number of medium-risk areas to 12, local authorities said on Sunday.

Since four cold-chain workers first tested positive on Dec. 15, Dalian has reported a total of 28 locally transmitted confirmed cases and 24 local asymptomatic cases, as of Saturday, during a new round of the epidemic.

The city had completed nucleic acid tests on all its citizens, nearly 6.38 million people, Zhao Lian, deputy director of the Dalian municipal health commission, told a press briefing on Sunday.