China’s government has ordered a province of 24 million people into lockdown as it tries to contain a Covid-19 outbreak that has spread to multiple locations. Authorities reported 1,437 new cases across the country, including 895 in Jilin province, which was put under lockdown measures. People living in the province have been banned from moving around, and anyone wanting to leave the province must apply for permission from police. Restrictions were already in place in two cities, Jilin and Changchun. The industrial province sent 7,000 reservists to help with the response, from keeping order and registering people at testing centres to using drones to carry out aerial spraying and disinfection, the state broadcaster CCTV reported. On Sunday a government notice said all residential communities in Shenzhen, a city of 17.5 million people, were being placed under “closed management”, meaning they would be locked down. Every resident would undergo three rounds of testing, for which they were allowed to leave their homes, and all buses and subways were suspended. All businesses in the finance and technology hub, which borders Hong Kong, were ordered to close or work from home unless they supplied food, utilities or other necessities, according to the notice. On Monday afternoon Foxconn, which produces iPhones for Apple, announced it was among businesses suspending operations in Shenzhen. Its larger production site in Zhengzhou remains open, and the company said it would reopen when advised by the local government. No one can leave the city except in special circumstances and with a negative test result obtained within 24 hours prior to exit. Local communities and residences had established monitoring teams with a “warm-hearted service hotline”, it said. The restrictions are due to stay in place until at least 20 March, adding Shenzhen to a number of other cities under various restrictions, including China’s most populous city, Shanghai. Some residents of Cangzhou, south of Beijing, were also told to stay at home after nine cases were reported there, according to a government notice. Authorities in Jilin province are stepping up anti-disease measures after concluding their earlier response was inadequate, according to Zhang Yan, the deputy director of the provincial health commission. “The emergency response mechanism in some areas is not sound enough,” Zhang said at a news conference. The mayor and deputy party chief of Jilin city, the director of the Changchun health commission and the party chief at a Jilin university were among at least 26 officials to be sacked or punished for their alleged poor responses to the current outbreak, state media reported. The case numbers reported among China’s 1.4 billion people are low compared with other countries, but represent the country’s worst outbreak since the start of the pandemic. China’s zero-Covid strategy of swiftly crushing outbreaks through resource-intensive mass testing and lockdowns has so far been successful. However, as in other countries, the emergence of the Omicron variant has challenged defences. Chinese authorities have for the first time approved antigen self-testing products to supplement the government-run nucleic acid testing. China is among a few governments around the world still committed to the zero-tolerance approach. Across the strait, Taiwan is reporting just a few – or zero – daily community cases and appears to have contained Omicron outbreaks. It is maintaining its strict border controls, and some social restrictions, and is yet to be faced with a large-scale Omicron outbreak. In Hong Kong the variant has overwhelmed the city and its government’s insistence on sticking to a strategy of elimination over mitigation. On Sunday it reported more than 32,400 cases. Hospitals have been swamped, with patient beds in lobbies and carparks. As of last week Hong Kong had the highest death rate in the developed world, inflaming criticism of the government for failing to adequately prepare for a large-scale outbreak during two years of being largely Covid-free. “People should not get the wrong impression that the virus situation is now under control,” said Dr Albert Au, an expert with the government’s Centre for Health Protection. “Once we let our guard down, it’s possible that [infections] will bounce back and rise again.” Zhang Wenhong, China’s top infectious disease expert, on Monday said Hong Kong’s outbreak was in the “early stage of an exponential rise”, and said it was inevitable that some would panic but people should retain confidence in the effectiveness of lockdowns, testing and restrictions. “As long as we slow down, the virus will not be fast,” he said. Zhang said opening up would be “disastrous” for China, with many elderly people unvaccinated, but once the outbreak was contained there must be a “moderate and sustainable” lasting strategy. “We must take advantage of the rare opportunity period and window period brought about by the inevitable social reset, and prepare more complete, smart, and sustainable coping strategies,” he said.