Citizens queue up at midnight at a nucleic acid testing site in Chengguan district of Lanzhou city, Northwest China's Gansu province, Oct 21, 2021. As of 8 pm on Oct 20, Lanzhou has registered a total of eight locally transmitted confirmed COVID-19 cases and one asymptomatic case since new local infections were reported. Local authorities set up hundreds of nucleic acid testing sites to provide 24-hour testing services for the residents. [Photo/Xinhua]
A medical worker collects swab samples at a nucleic acid testing site in Chengguan district of Lanzhou city, Northwest China's Gansu province, Oct 21, 2021. [Photo/Xinhua]
Medical workers collect swab samples at a nucleic acid testing site in Chengguan district of Lanzhou city, Northwest China's Gansu province, Oct 21, 2021. [Photo/Xinhua]
A medical worker collects swab samples at a nucleic acid testing site in Chengguan district of Lanzhou city, Northwest China's Gansu province, Oct 21, 2021. [Photo/Xinhua]
Aerial photo taken on Oct 21, 2021 shows citizens queuing up at midnight at a nucleic acid testing site in Chengguan district of Lanzhou city, Northwest China's Gansu province. [Photo/Xinhua]
Medical workers work overnight collecting swab samples at a nucleic acid testing site in Chengguan district of Lanzhou city, Northwest China's Gansu province, Oct 21, 2021. [Photo/Xinhua]
Medical workers collect swab samples at a nucleic acid testing site in Chengguan district of Lanzhou city, Northwest China's Gansu province, Oct 21, 2021. [Photo/Xinhua]
