China's major tech hub of Shenzhen on Monday came under a citywide lockdown in the face of rising coronavirus cases in the country's mainland and Hong Kong.

Shenzhen's 17 million residents have been asked to stay at home through March 20, during which the southern city, bordering Hong Kong, will carry out three rounds of mass testing and suspend public transport services, according to a local government notice.

Local residents queue up for COVID-19 tests on March 13, 2022, in Shenzhen, China. (VCG/Getty/Kyodo)

The lockdown comes a day after the Chinese government said 3,122 COVID-19 cases, including asymptomatic infections, were confirmed in the country's mainland on Saturday, more than double that of the previous day.

Hong Kong health authorities reported 32,430 new positive cases on Sunday, while the daily count in Shenzhen remains less than 100 but is gradually rising.

With its tough "zero-COVID" policy, China, which first detected the virus in late 2019, has far fewer cases than most countries.

But other areas of China, including Shanghai and Qingdao, have also rolled out stricter measures against the spread of the virus as it grapples with the worst outbreak in two years. All facilities in Shenzhen are now closed with the exception of supermarkets, pharmacies, medical institutions and eateries with takeout services.

Across mainland China, the northeastern province of Jilin has been the hardest hit by the resurgence of infections, accounting for about 70 percent of the daily caseload.

Changchun, the provincial capital, was placed under lockdown recently, with Toyota Motor Corp. saying Monday operations at its joint venture plant in the city of about 9 million people are to be suspended.


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