Shortages of food and medicine have left residents in China’s biggest city desperate and frustrated as authorities struggle to gain control of a Covid-19 outbreak.

Shanghai, which has been forced to follow Beijing’s tough “dynamic zero” Covid strategy, implemented two four-day lockdowns of each side of the Huangpu river. But as the caseload of the infectious Omicron variant rose rapidly, authorities extended restrictions on parts of the eastern Pudong area, which includes the city’s financial district.

Cries for help littered social media this weekend before being deleted by censors, as the city’s case count overtook that of Hong Kong, which recorded the world’s highest fatality rate in March.

Residents on social media said online grocery stores had run out of food while others complained that they could not buy their regular medication. “Who can tell me how to get medicine? I am so hopeless. I want to leave Shanghai,” said one resident.

Some Shanghainese, who have been unable to leave their homes for more than two weeks owing to restrictions that predated the lockdown because of positive cases in their buildings, have relied on government grocery deliveries.

Parents also pleaded for help after being separated from their young children if they or their child tested positive. Zeng Qun, deputy head of the Shanghai Civil Affairs Bureau, said temporary guardians would be found for children who were not infected but were forced to stay at home alone after their parents were sent to quarantine centres, state media reported.

EU nations last week called on local authorities to stop separating children from their parents and to ensure appropriate care for those facing non-Covid emergency medical issues.

In a reflection of how contentious the country’s elimination policy has grown, a recorded conversation, allegedly between a Shanghai health official and a resident, was widely shared.

The official complained about politicized decision-making.