Protests in China against heavy COVID-19 restrictions spread to major city, Shanghai on Sunday, with demonstrators also gathering at one of Beijing’s most prestigious universities after a deadly fire in the country’s far west sparked widespread anger.

The wave of civil disobedience occurred as well as elsewhere in Beijing and in other cities, has reached unprecedented levels in mainland China.

As a large group of police looked on, the crowd held up blank sheets of paper — a protest symbol against censorship. Later on, they shouted, “lift lockdown for Urumqi, lift lockdown for Xinjiang, lift lockdown for all of China!,” according to a video circulated on social media.

China has stuck with Xi’s signature zero COVID-19 policy even while much of the world tries to coexist with the coronavirus. While low by global standards, China’s cases have hit record highs for days, with nearly 40,000 new infections on Saturday.

China defends the policy as life-saving and necessary to prevent overwhelming the healthcare system. Officials have vowed to continue with it despite the growing public pushback and its mounting toll on the world’s second-biggest economy.

Videos from Shanghai showed crowds facing police and chanting “Serve the people”, “We want freedom,” and “We don’t want health codes”, a reference to the mobile phone apps that must be scanned for entry into public places across China.

The Shanghai government did not immediately respond to a request for comment on Sunday.

The city’s 25 million people were put under lockdown for two months earlier this year, provoking anger and protests.

Chinese authorities have since then sought to be more targeted in their COVID-19 curbs, an effort that has been challenged by the surge in infections as the country faces its first winter with the highly transmissible Omicron variant.

In Beijing on Saturday, some residents under lockdown were able to successfully confront and pressure local officials into lifting curbs ahead of schedule.

One video shared with Reuters showed Beijing residents marching in an unidentifiable part of the capital on Saturday, shouting “End the lockdown!”