SHANGHAI — Protesters angered by strict anti-virus measures called for China’s powerful leader to resign, an unprecedented rebuke as authorities in at least eight cities struggled to suppress demonstrations Sunday that represent a rare direct challenge to the ruling Communist Party.

Police using pepper spray drove away demonstrators in Shanghai who called for Xi Jinping to step down and an end to one-party rule, but hours later people rallied again in the same spot. Police again broke up the demonstration, and a reporter saw protesters under arrest being driven away in a bus.

The protests — which began Friday and have spread to cities including the capital, Beijing, and dozens of university campuses — are the most widespread show of opposition to the ruling party in decades.

In a video of the protest in Shanghai verified by The Associated Press, chants against Xi, the most powerful leader since at least the 1980s, and the Chinese Communist Party sounded loud and clear: “Xi Jinping! Step down! CCP! Step down!”

Three years after the virus emerged, China is the only major country still trying to stop transmission of COVID-19. Its “zero COVID” strategy has suspended access to neighborhoods for weeks at a time. Some cities carry out daily virus tests on millions of residents.

That has kept China’s infection numbers lower than those the United States and other major countries, but public acceptance has worn thin. People who are quarantined at home in some areas say they lack food and medicine. The ruling party faced public anger following the deaths of two children whose parents said anti-virus controls hampered efforts to get medical help.

The current protests erupted after a fire broke out Thursday and killed at least 10 people in an apartment building in the city of Urumqi in the northwest, where some have been locked in their homes for four months. That prompted an outpouring of angry questions online about whether firefighters or people trying to escape were blocked by locked doors or other restrictions.

About 300 demonstrators gathered late Saturday in Shanghai, most of whose 25 million people were confined to their homes for almost two months starting in late March.

On a street named for Urumqi, one group of protesters brought candles, flowers and signs honoring those who died in the blaze. Another group, according to a protester who insisted on anonymity, was more active, shouting slogans and singing the national anthem.

That protester and another, who gave only his family name, Zhao, confirmed the chants against Xi, who has awarded himself a third five-year term as leader of the ruling party and who some expect to try to stay in power for life. Like others who spoke to the AP, the protesters didn’t want to be identified due to fear of arrest or retaliation.

The atmosphere of the protest encouraged people to speak about topics considered taboo, including the 1989 crackdown on the Tiananmen Square pro-democracy protests, the protester who insisted on anonymity said.

Some called for an official apology for the deaths in the fire in Urumqi in the Xinjiang region. One member of Xinjiang’s Uyghur ethnic group, which has been the target of a security crackdown that includes mass detentions, shared his experiences of discrimination and police violence.

“Everyone thinks that Chinese people are afraid to come out and protest, that they don’t have any courage,” said the protester, adding it was his first time demonstrating. “Actually in my heart, I also thought this way. But then when I went there, I found that the environment was such that everyone was very brave.”

The scene turned violent early Sunday. Hundreds of police broke up the more active group before they came for the second as they tried to move people off the main street. The protester said that he saw people being taken away, forced by police into vans, but could not identify them.