London police said they arrested 10 people and four officers were injured as they broke up a thousands-strong demonstration against British coronavirus restrictions Saturday.
Skirmishes broke out as officers moved in with batons to disperse the more than 10,000 protesters gathered on central Trafalgar Square, who were not sticking to infection control measures, the Metropolitan Police said on Twitter.
"Sadly, four of our officers have been injured, two require hospital treatment," the Met wrote.
A dozen officers were injured in a similar protest last week.
Among the Saturday crowd was David Icke, a prominent conspiracy theorist who has drawn attention in the past by suggesting the world is secretly governed by reptilian humanoids, including the British royal family.
Some people in the crowd carried signs opposing any potential vaccine against the coronavirus.
Prime Minister Boris Johnson on Saturday pledged new support for the World Health Organization's effort to develop a vaccine and called those rejecting a potential inoculation "nutjobs".
Local infection control restrictions now extend to one in four people in Britain in an attempt to contain a mounting second wave of the virus, which has claimed 42,000 lives in the country so far - Europe's highest toll.
This week, Johnson's government imposed a ban on gatherings of more than six people and ordered pubs and restaurants to close at 10:00 pm in a bid to slow the spread.