Shanghai city reported Monday its first Covid-related deaths since the latest wave of lockdowns began in earnest in late March.

Three people have died as of Sunday, the city said, attributing the deaths to preexisting health conditions. All three people who died were elderly, had underlying diseases such as diabetes and hypertension, and had not been vaccinated against the coronavirus, city Health Commission inspector Wu Ganyu told journalists.

The officials said two of the dead were women aged 89 and 91, while the third was a 91-year-old man.

While China has an overall vaccination rate of around 90%, a low rate among the elderly remains a concern. Only 62% of Shanghai residents over age 60 have been vaccinated, according to the latest data available.

The eastern business hub has groaned under a patchwork of restrictions since March, with many of the city's 25 million residents confined to their homes as daily caseloads topped 25,000 - a modest figure by global standards but virtually unheard of in China.

Many inhabitants have chafed under the curbs, flooding social media with complaints of food shortages, spartan quarantine conditions, and heavy-handed enforcement, and circulating footage of rare protests faster than government censors can delete them.

But officials have remained inflexible, vowing to continue isolating anyone who tests positive regardless of whether they show signs of the disease.