Beijing will conduct mass testing of most of its 21 million people as a new COVID-19 outbreak sparks stockpiling of food by residents worried about the possibility of a Shanghai-style lockdown.

The Chinese capital began mass testing people in one of its 16 districts where most of the new cases have been found.

The city also imposed lockdowns on individual residential buildings and one section of the city. Late in the day, health officials said the testing would be expanded on Tuesday to all but five outlying districts.

While only 70 cases have been found since the outbreak surfaced Friday, authorities have rolled out strict measures under China’s “zero-COVID” approach to try to prevent a further spread of the virus.

Some residents worked from home and many stocked up on food as a safeguard against the possibility they could be confined indoors, as has happened in multiple cities, including the financial hub of Shanghai.

The city of Anyang in central China and Dandong on the border with North Korea became the latest to start lockdowns as the Omicron variant spreads across the country of 1.4 billion people.

Shanghai, which has been locked down for more than two weeks, reported more than 19,000 new infections and 51 deaths in the latest 24-hour period, pushing its announced death toll from the ongoing outbreak to 138.

Beijing residents snapped up rice, noodles, vegetables and other food items as long lines formed in supermarkets and store workers hastily restocked some empty shelves. State media issued reports saying supplies remained plentiful despite the buying surge.

Beijing health officials said 29 new cases had been identified in the 24 hours through 4pm on Monday, raising the total to 70 since Friday.

The city has ordered mass testing across sprawling Chaoyang district, where 46 of the cases have been found. The 3.5 million residents of Chaoyang, as well as people who work in the district, need to be tested on Monday, Wednesday and Friday.

Shanghai has buckled under a strict lockdown that has driven residents to band together to get food delivered through group buying. Goods have backed up at the port of Shanghai, affecting supplies and factory production and putting a crimp on economic growth.

– AAP