TAIWAN, China (AP) — Volunteers and government workers in Shanghai erected metal barriers in multiple districts to block off small streets and entrances to apartment complexes, as China hardens its strict “zero-COVID” approach in its largest city despite growing complaints from residents.

In the city’s financial district, Pudong, the barriers — thin metal sheets or mesh fences — were put up in several neighbourhoods under a local government directive, according to Caixin, a Chinese business media outlet. Buildings where cases have been found, sealed up their main entrances, with a small opening for pandemic prevention workers to pass through.

China reported 21,796 new community transmitted COVID-19 infections on Sunday, with the vast majority being asymptomatic cases in Shanghai. Across the country, many cities and provinces have enforced some version of a lockdown in an attempt to slow the spread of the virus.

The latest outbreak, driven by the highly contagious omicron variant, has spread nationwide, but has been particularly large in Shanghai. The city, a financial hub with 25 million residents, has counted hundreds of thousands of cases but fewer than 100 deaths since the outbreak began nearly two months ago.

In Shanghai, authorities reported 39 new COVID-19 deaths, raising the official death toll to 4,725 as of the end of Saturday, the National Health Commission said Sunday.

The city’s lockdown has drawn global attention for its strict approach and sometimes dangerous consequences. Many residents in the city have had difficulties getting groceries, resorting to bartering and bulk buying. Others have been unable get adequate medical attention in time, owing to the strict controls on movement.

Chinese authorities have continued to say that the “zero-COVID” strategy is the best way forward given low vaccination rates in people over age 60, and that omicron would result in many deaths and severe illnesses if the country ended its strict approach.