XI'AN — Xi'an, capital of Northwest China's Shaanxi province, imposed closed-off management for communities and villages on Dec 23, in an effort to curb the spread of the latest COVID-19 resurgence.

All communities, villages and working units have been closed off since Dec 23, and residents have been asked not to leave the city unless absolutely necessary.

Long-distance passenger transport lines have been suspended, with the exception of freight vehicles transporting epidemic prevention materials and daily necessities.

Taxis and drivers working for online ride-hailing platforms are forbidden from entering medium or high-risk areas, or traveling outside the city.

A total of 127 people tested positive for the virus during the second citywide nucleic acid testing, according to data released on Thursday by the city's COVID-19 prevention and control headquarters.

At 8 am on Dec 23, the city launched a new round of testing, with more than 4 million people sampled by noon.

A Xinhua correspondent visits a nucleic acid testing lab in the city to see how it could conduct the nucleic acid testing with such a speed.