LANZHOU -- Authorities in Lanzhou, capital of Northwest China's Gansu province, have issued orders to place all local residential communities under closed management amid the latest efforts to contain the COVID-19 spread.

Each residential community will have just one open entrance and the entry and exit of residents will be strictly controlled except under special circumstances, according to the municipal leading group for COVID-19 prevention and control.

By Monday, Gansu Province had a total of 51 confirmed COVID-19 cases. Health authorities in Lanzhou are conducting a third mass nucleic acid testing.