China has been rocked by some of its most significant acts of civil disobedience in years after vigils in Shanghai and other big cities to mark a deadly fire in Xinjiang region turned into protests over Xi Jinping’s draconian zero-Covid policies.

Social media posts have blamed the deaths of 10 people in the blaze on Thursday in an apartment block in Urumqi, the capital of Xinjiang, on Covid-19 restrictions, despite denials from authorities.

At Wulumuqi road in Shanghai, named after the Xinjiang city, hundreds of people attended a vigil late on Saturday night. Video footage and photographs of the incident, verified by the FT, showed clashes between police and protesters in the early hours of Sunday.

Earlier, some protesters were standing on police cars and others chanted “we don’t want PCR tests”. Some shouted for the Chinese Communist party and President Xi Jinping to “step down”.

The expression was a direct echo of a rare protest when a poster was hung on a bridge in Beijing last month, which included a list of slogans based around the expression “[we] don’t want”, including “we don’t want lockdowns, we want freedom”.

“I know what I’m doing is very dangerous, but it’s my duty,” said one student who rushed to attend the vigil after seeing it online. Another said the event began as a quiet commemoration of the people who died in the fire in Urumqi, but later got “out of control”.

On Sunday afternoon, hundreds of people again gathered at the site of the vigil, with some carrying white flowers, a symbol of mourning in Chinese culture. Police closed the nearby roads, removed the flowers from a lamppost and told people to go home.

China has sought to keep the virus at bay through strict lockdowns and quarantine measures for nearly three years but the policy is coming under immense pressure from rising cases, popular discontent and a slowing economy. On Sunday, authorities reported the most daily infections on record for the fourth consecutive day, with the tally now close to 40,000.

Elsewhere on Chinese social media, footage of protests, initially of groups of people in Urumqi from Friday night but subsequently across the country, circulated widely but were also censored.

Videos showed students gathering at a vigil at the Communication University of Nanjing, while elsewhere images also emerged of a similar vigil at a university in Wuhan.

In Beijing’s Peking University, images circulated of graffiti on steps repeating some of the slogans from the bridge in October, including “we don’t want PCR tests, we want food”.

One student at the university said the graffiti was partly removed early on Sunday morning, and that a food truck was parked in front of it to block it from view.

Images showing protesters holding up white sheets of paper, to symbolise censorship, were spread widely on social media.

One person who attended the vigil in Shanghai confirmed that white pieces of paper were also held up there. They said one police officer told the crowd that he understood how everybody feels, but suggested they “keep it at the bottom of their hearts”.

Sheena Chestnut Greitens, a China expert and Jeane Kirkpatrick Visiting Fellow at the American Enterprise Institute, said the widespread unrest could “become a serious test of the tools of social control developed under Xi”.

Authorities are grappling with Covid outbreaks in many large cities, including Guangzhou, Chongqing and Beijing. China’s previous outbreaks have been successfully suppressed but they typically took place in single cities, such as in Shanghai early this year.

In Beijing, where restrictions have been ramped up in recent days but authorities have still stopped short of a full citywide lockdown, some residents confronted officials over compound-level closures to negotiate their release.

There were signs of people drawing on the protests to counter such restrictions elsewhere in China. A Shenzhen resident in his thirties told the FT that the sight of protests in Urumqi and Beijing provided “inspiration” after peaceful negotiations with officials to lift a lockdown of their compound failed.

He said he and his neighbours gathered at the gates and shouted “set us free” and that the restrictions were subsequently lifted.

“We were copying and pasting what Beijing and Urumqi residents did and it worked,” he said.

Additional reporting by Cheng Leng in Hong Kong, Edward White in Seoul and Joe Leahy in Beijing