Police officers clash with a protester during an anti-coronavirus restrictions protest in Trafalgar Square in London, Britain, on Sept. 26, 2020. Police has shut down an anti-coronavirus restrictions protest in central London on Saturday because crowds have not complied with social distancing rules. At least three protesters and one police officer were reportedly injured and treated by medical staff after they clashed at the anti-lockdown protest in Trafalgar Square. (Photo by Ray Tang/Xinhua)

Police has shut down an anti-coronavirus restrictions protest in central London on Saturday because crowds have not complied with social distancing rules.

At least three protesters and one police officer were reportedly injured and treated by medical staff after they clashed at the anti-lockdown protest in Trafalgar Square.

Thousands had gathered in the "we do not consent" rally to protest against government rules, with very few wearing masks.

Protesters take part in an anti-coronavirus restrictions protest in Trafalgar Square in London, Britain, on Sept. 26, 2020. Police has shut down an anti-coronavirus restrictions protest in central London on Saturday because crowds have not complied with social distancing rules. At least three protesters and one police officer were reportedly injured and treated by medical staff after they clashed at the anti-lockdown protest in Trafalgar Square. (Photo by Ray Tang/Xinhua)

 
BBC reported police officers penned the crowd in Trafalgar Square as water and bottles were thrown at them by demonstrators, while police removed sound equipment and used batons against protesters, leaving some with visible injuries.

A Metropolitan Police statement said that those who stayed could face criminal penalties because they "have not complied with the conditions of their risk assessment and are putting people in danger of transmitting the virus".

"This has voided their risk assessment and we have informed the event organisers they are no longer exempt from the regulations."

Police officers detain a protester during an anti-coronavirus restrictions protest in Trafalgar Square in London, Britain, on Sept. 26, 2020. Police has shut down an anti-coronavirus restrictions protest in central London on Saturday because crowds have not complied with social distancing rules. At least three protesters and one police officer were reportedly injured and treated by medical staff after they clashed at the anti-lockdown protest in Trafalgar Square. (Photo by Ray Tang/Xinhua)

 
The rally came a week after a separate event which saw more than a dozen officers injured and more than 32 arrests were made.

Rules in England limit indoor and outdoor gatherings to six people. Protests are exempt from the rule-of-six restrictions, but demonstrators must maintain social distance and a risk assessment must be submitted by organizers.

On Friday, London was placed on the national COVID-19 "watch list" as an area of high concern. As the coronavirus cases continue to rise in the British capital, the mayor of London, Sadiq Khan, warned that London is "at a very worrying tipping point right now."

Police officers detain a protester during an anti-coronavirus restrictions protest in Trafalgar Square in London, Britain, on Sept. 26, 2020. Police has shut down an anti-coronavirus restrictions protest in central London on Saturday because crowds have not complied with social distancing rules. At least three protesters and one police officer were reportedly injured and treated by medical staff after they clashed at the anti-lockdown protest in Trafalgar Square. (Photo by Ray Tang/Xinhua)

 
Meanwhile, countries, such as Britain, China, Russia and the United States, are racing against time to develop coronavirus vaccines.

The British government's Chief Scientific Adviser Patrick Vallance said Monday that it is possible that some vaccine could be available in small amounts later this year, but it is more likely that a vaccine will be available early next year, although that is not guaranteed.  

A protester holding a placard takes part in an anti-coronavirus restrictions protest in Trafalgar Square in London, Britain, on Sept. 26, 2020. Police has shut down an anti-coronavirus restrictions protest in central London on Saturday because crowds have not complied with social distancing rules. At least three protesters and one police officer were reportedly injured and treated by medical staff after they clashed at the anti-lockdown protest in Trafalgar Square. (Photo by Ray Tang/Xinhua)