Tianjin, a major port city in China about a 30-minute train ride away from Beijing, has begun mass testing for its 14 million residents on Jan. 9, after detecting a cluster of 20 Covid-19 cases, the Associated Press (AP) reported.

The citywide testing is expected to be completed over two days.

The first two cases that were detected were both infected with the Omicron variant. One of them is a 10-year-old girl, and the other is a 29-year-old woman working at an after-school centre.

After testing their close contacts, another 18 positive cases among staff, students, and parents were reportedly detected, while 767 people tested negative as of Jan. 8.

It is currently unknown if there are any Omicron cases among the 18 individuals, according to Chinese state-controlled media Global Times (GT).

No lockdown yet

According to The Guardian, residents of Tianjin have been advised to stay at home or near their homes, to be available for Covid-19 screening.

The city's residents will only obtain a "green" code on their Covid-19 tracing app after they test negative for the virus, AFP reported.

The "green" code is needed to board public transport and access various public spaces in China.

As of Jan. 8, the city has placed 75,680 people in quarantine, though the city has yet to order a lockdown, GT reported.

However, 29 residential communities in Tianjin were reportedly sealed off on Jan. 8, and commuters between Tianjin and Beijing are encouraged to work from home.

The Tianjin Binhai International Airport reportedly cancelled 144 flights on Jan. 9, and two subway lines will be partially closed from Jan. 9 onwards.

An official said more cases are expected to be found, and the recent outbreak may have spread among the local community.

Rushed to stock up on food

Speaking to GT, Tianjin residents said there were people who rushed to stock up on food for fear of a lockdown.

Less than a week ago, over one million people in Yuzhou city were locked down after three asymptomatic Covid-19 cases were detected in the city.

Meanwhile, Xi'an imposed a lockdown on its 13 million residents on Dec. 23 after a surge of Covid-19 infections.

People in Xi'an were not allowed to leave their homes, and there were complaints of shortage of food and essential supplies.

According to the Financial Times, a pregnant woman in the city recently suffered a miscarriage after she was denied entry to a hospital.

The woman's niece said her aunt was not admitted after arriving at the hospital as her Covid-19 test result had expired two hours before that.

Lunar New Year and Winter Olympics

Due to a large number of commuters working and living in Tianjin and Beijing, an immunologist warned that the outbreak in Tianjin posed risks to the Chinese capital, GT reported.

China has consistently pursued a "zero-Covid" policy, with strict border restrictions, targeted lockdowns, and lengthy quarantine periods.

The country is preparing for the Beijing Winter Olympics, which will take place from Feb. 4 to Feb. 20.

Officials are also under pressure as China's busiest travel season — the Lunar New Year — is just around the corner, according to Bloomberg.

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