Many of the city's 26 million people have been forced to stay at home under China's zero-COVID policy, with fences up to two metres high being erected around housing blocks and some streets being closed off entirely on Saturday.

Photos of the fences were posted on social media platform Weibo and some users reacted angrily.

Read more: China's coronavirus zero policy is actually two policies - it just depends where you are

One wrote: "This is so disrespectful of the rights of the people inside - using metal barriers to enclose them like domestic animals."

Videos were posted showing residents protesting from their balconies while the fences were set up, and also some footage showing people trying to pull down the fences themselves.

In Shanghai, neighbourhoods are divided into three categories based on the risk of transmission, and these categories dictate how free people are to go about their daily lives.

Shanghai is doing daily city-wide COVID tests and all positive cases are forced into quarantine centres.

it has also been reported that whole communities are being moved, including people who do not have COVID, with authorities saying that this allows homes to be dis-infected.

Dozens have died of the virus in Shanghai during this outbreak but some doubt the figures

Some 39 people were reported to have died of COVID-19 in Shanghai on 23 April, compared to 12 a day earlier, official figures said.

But the city did not report any deaths in the first few weeks of the outbreak, leaving some to doubt the accuracy of the figures.

The 87 deaths reported during the outbreak have all taken place in the past seven days, authorities have said.

Some 19,657 new locally-transmitted asymptomatic cases and 1,401 symptomatic cases were recorded on 23 April, both figures down slightly on the previous day.

There were 280 cases from outside quarantined areas, compared to 218 the previous day.

Lockdown badly-hitting China's economic hub

For many of Shanghai's residents, the lockdown has lasted more than three weeks, badly hitting China's most important economic hub, causing people to lose wages, families to be separated, and many people to experience food shortages and other supplies.

Anger is growing, although venting online is difficult in a country where government censors are constantly on the look-out for any criticism of political leaders.

Many residents posting online use euphemisms, while videos of Do You Hear The People Sing? - a revolutionary anthem from the musical Les Miserables have been widely re-posted.

The title of the musical had more than 90 million mentions on We Chat on Saturday.

But the end could be a long way away - other Chinese cities that were under lockdown only started to ease restrictions after the number of cases fell to zero.