Beijing launched mass coronavirus testing on Tuesday for nearly all its 21 million residents, as fears grew that the Chinese capital may be placed under a strict lockdown like Shanghai.

Under its zero-Covid policy, China has used lockdowns, mass testing and travel restrictions to stamp out infections.

Its biggest city, Shanghai, has been almost entirely locked down for weeks, and the mass testing order in Beijing has sparked worries the capital will be placed under similar restrictions.

Beijing has launched mass coronavirus testing for nearly all its 21 million residents as fears grow that the Chinese capital might be placed under a strict lockdown like Shanghai
Beijing has launched mass coronavirus testing for nearly all its 21 million residents as fears grow that the Chinese capital might be placed under a strict lockdown like Shanghai AFP / Noel Celis

"Shanghai's situation has gone beyond everyone's imagination, and many people think it's absurd that a modern metropolis... has handled the situation like that," said Beijing resident Ms Zhao as she did her regular shopping at a supermarket.

"I believe our situation will not be as bad... but to be honest, we also bought some rice, noodles, grains and oil. We've made preparations for at least one to two weeks," the 35-year-old human resources professional told AFP.

Beijing has ordered residents of the 12 central districts home to most of its population to undergo three rounds of testing after dozens of infections were found in recent days.

The capital's most populous district, Chaoyang, was the first to order mass testing from Monday, with people waiting in long lines to be swabbed by health workers in protective gear.

Shanghai, China's largest city, has been battling a major Covid outbreak for weeks
Shanghai, China's largest city, has been battling a major Covid outbreak for weeks AFP / Hector RETAMAL

Eleven more districts began testing on Tuesday.

The testing order for Chaoyang sparked panic buying on Sunday night, with residents lining up at supermarkets with full carts as state media tried to reassure the public there were plentiful supplies.

Beijing residents told AFP they feared a repeat of the sudden lockdown in Shanghai, where people have struggled to obtain food and medical care for non-Covid conditions.

Several residential compounds have already been sealed off in Chaoyang.

Beijing's most populous downtown district Chaoyang was the first to order mass testing from Monday, with people waiting in long lines to be swabbed by health workers
Beijing's most populous downtown district Chaoyang was the first to order mass testing from Monday, with people waiting in long lines to be swabbed by health workers AFP / Jade GAO

One resident, who declined to be identified for fear of reprisal, told AFP he felt "a little anxious" after fences were suddenly put up in his neighbourhood.

Residents in his building were ordered Monday night to stay home for at least 14 days after one neighbour tested positive.

"I'm worried that if we need medicine or other items in the future, we won't be able to get them delivered," he said.

Meanwhile, Beijing suspended large gatherings such as wedding banquets, closed theatres, and ordered a halt in some construction projects.

Rental bikes are seen blocking a street in Beijing's Chaoyang district
Rental bikes are seen blocking a street in Beijing's Chaoyang district AFP / STR

Many of the new infections were linked to one wedding party, officials told reporters, saying efforts to control the spread of the virus were at a "critical stage".

They urged residents to wear stronger N95 masks.

Multiple residents took to social media to lament the last-minute postponement of their weddings.

"I'll develop psychological problems if this goes on," wrote a woman who said she would have to delay her wedding, planned for the upcoming May national holiday -- a popular time for couples tying the knot.

The capital reported 33 new cases Tuesday, a fraction of Shanghai's daily tally of 16,000 infections and 52 new deaths.

But Beijing officials are anxious to avoid a spiralling outbreak.

They have urged companies to allow employees to work from home and suspended local group tourism ahead of the May national holiday.

Authorities have urged residents not to leave Beijing unless necessary.

Beijing's measures are mild, however, compared with actions taken elsewhere, Pinpoint Asset Management chief economist Zhiwei Zhang said in a note.

"I am surprised that the government did not impose restrictive policies in Beijing as harshly and quickly as in other cities that experienced similar outbreaks in recent weeks," he wrote.

Authorities are increasingly struggling with the impact of strict zero-Covid protocols on the economy, especially when outbreaks appear in the country's most important cities.

Concerns have also grown about how China's Covid-19 policies could impact the global economy, especially supply chains.

The city of Baotou in China's Inner Mongolia region -- a major supplier of rare earths -- said Monday that after the detection of two virus cases, all residents must stay home, with each household only sending one member out each day for necessities.

China's central bank promised to "increase support" for the economy on Tuesday, particularly for smaller businesses affected by the pandemic.