Shanghai reported that 39 Covid deaths on Sunday, official data showed, were the highest daily number since the ban, and China's capital, Beijing, had warned of a "terrible" epidemic.
Shanghai-based anti-COVID-19 authorities have erected mesh barriers outside certain residential buildings, sparking a new public outcry over the closure that forced many of the city's 25 million people to stay at home.
Pictures of workers in white hazmat suits closing the doors of houses and closing all two-meter-green fenced roads spread on social media on Saturday, sparking questions and complaints from residents.
"This is a violation of the rights of insiders, using metal barriers to keep them as pets," said one user on social media site Weibo.
The second-largest economy in the world has been struggling to end its worst Covid-19 outbreak in two years with a tight-closing playbook and mass test as it adheres to a strict zero-Covid policy, which takes a toll on business and social behavior. .
The Shanghai business district has been almost completely closed since the beginning of the month, with many chains available, many residents trapped in their homes for as long as it has been the cause of the outbreak.
The Chinese capital announced its first death on April 18, although it reported thousands of cases each day in recent weeks.
It reported that 39 people had died on Sunday, the National Health Commission said, bringing the total to 87, and the country had received about 22,000 new cases of the virus.
Shanghai, China's largest city and most important economic center, is fighting the outbreak of COVID-19 in the country with a policy of eradication that seeks to investigate, track and enforce all positive cases in isolated areas.
The closure, which has plagued many residents for more than three weeks, has exacerbated frustrations over food security and health care, lost wages, family breakdown, solitary confinement, and cybercrime testing.
Health official Pang Xinghuo said the first impression suggests that Covid has been "invisiblely distributed" in the capital for a week now, affecting "schools, tourist groups and many families".
"The risk of secrecy is high, and the situation is dire," Tian Wei of the Beijing Municipal Party Committee told a news conference.
"The whole city of Beijing must take immediate action."
