A coach turned into a mobile laboratory for COVID-19 nucleic acid tests is put into operation at Wulin Square in Hangzhou, Zhejiang province on Dec 14. [Photo/CFP]

A coach that has been transformed into a mobile laboratory for COVID-19 nucleic acid tests was put into operation at Wulin Square in Hangzhou, Zhejiang province on Dec 14, local media outlets reported.

Residents living and working in the surrounding seven communities can now undergo free nucleic acid tests without having to visit local hospitals.

"I work at the nearby Hangzhou Tower shopping mall. I came as soon as I got the call. It's very convenient for me to walk over here and I hope there will be more facilities like this in the future," said a security guard at the mall.

The lab, which is able to collect 4,000 samples per day, can produce test results in as quickly as 100 minutes. If necessary, the lab can be moved to other locations that require emergency testing.

People wait in line at Wulin Square in Hangzhou on Dec 14 for nucleic acid testing. [Photo/CFP]