Protesters rallying against continuing Covid restrictions in China are using blank sheets paper and mathematical equations to signal their dissent under strict authoritarian rule.
Demonstrators have been pictured holding up sheets of paper and signs bearing complex mathematical equations as they rally in the streets of mainland China and Hong Kong.
Crowds angered by continuing Covid restrictions have called for Chinese leader Xi Jinping to resign, in the country's biggest show of public dissent in decades.
Chinese universities sent students home while police fanned out in Beijing and Shanghai to prevent more protests on Tuesday.
Authorities had eased some controls after demonstrations in at least eight mainland cities and Hong Kong, but protesters have continued to find inventive ways to express their dissent amid an environment of sweeping censorship.
Hong Kong activist Nathan Law, was among those highlighting university students' use of advanced equations to subtly communicate their defiance.
He posted a picture of Beijing's Tsinghua University students holding signs bearing examples students of physical cosmology would recognise as an example of the Friedmann equations— a set of equations that govern the expansion of space in models of the universe.
The name of the equation sounds like "freed man," he explained on Twitter, adding it was "a spectacular and creative way to express, with intelligence."
Social media users posting pictures of the protests in Beijing also zeroed in on demonstrators' use of the equations.
Despite the growing dissent, Chinese authorities showed no sign of backing off their broader 'zero-Covid' strategy that has confined millions of people to their homes for months at a time.
Security forces have detained an unknown number of people and stepped up surveillance in the country, where state censorship heavily restricts opportunities to organise dissent.
Under pressure, the Chinese Communist Party promised last month to reduce disruption by changing quarantine and other rules.
But a spike in infections has prompted cities to tighten controls, fuelling public frustration.
Protests over the weekend were sparked by anger over the deaths of at least 10 people in a fire in China's far west last week.
The fire deaths prompted angry questions online about whether firefighters or victims trying to escape were blocked by anti-virus controls.
At an event in Hong Kong, about four dozen protesters held up blank sheets of paper and flowers in what they said was mourning for the fire victims in Urumqi and others who have died as a result of “zero Covid” policies.
Police cordoned off an area around protesters, who stood in small, separate groups to avoid violating pandemic rules that bar gatherings of more than 12 people. Police took identity details of participants but there were no arrests.
Hong Kong has tightened security controls and rolled back Western-style civil liberties since China launched a campaign in 2019 to crush a pro-democracy movement.
The territory has its own anti-virus strategy that is separate from mainland China.
Most protesters over the weekend in the mainland complained about excessive restrictions, but some also turned their anger at Xi, the nation's most powerful leader since at least the 1980s.
Widespread demonstrations are unprecedented in China since the army crushed the 1989 student-led pro-democracy movement in the deadly Tiananmen Square massacre in Beijing.
The BBC also criticised authorities after the arrest and alleged beating of one it journalists covering the Covid protests in Shanghai.
China’s ambassador to the UK has also been summoned to the Foreign Office amid a diplomatic row over the incident.
Foreign Secretary James Cleverly described the incident as "deeply disturbing," after protesters shared footage showing the broadcaster's camera-man Edward Lawrence being dragged away by police.
The BBC said Mr Lawrence was “arrested and handcuffed” while covering the protests in Shanghai.
“During his arrest he was beaten and kicked by police,” the broadcaster said. “This happened while he was working as an accredited journalist.”
The corporation said Chinese officials claimed the journalist was arrested “for his own good” in case he caught Covid from the crowd, adding: “We do not consider this a credible explanation.”
Chinese Ministry of Foreign Affairs spokesman Zhao Lijian said the BBC reporter failed to identify himself and “didn’t voluntarily present” his press credential.
“Foreign journalists need to consciously follow Chinese laws and regulations,” Zhao said.
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