Eight police officers have been injured after clashing with hundreds of anti-establishment protesters in Parliament Square on Bonfire Night.
Demonstrators wearing Guy Fawkes-style masks had gathered at nearby Trafalgar Square at the annual Million Mask March with some throwing fireworks at officers.
Footage posted on Twitter showed protesters at Parliament Square where they were pushed back by a line of officers wearing protective gear.
An effigy of Boris Johnson was burned while many of the demonstrators taking part in the event held signs protesting against the coronavirus lockdown.
The Metropolitan police said 12 arrests were made. It wrote on Twitter: “A total of 12 arrests were made while policing tonight’s demonstrations across London. Those arrests were for a variety of offences. Eight of our officers were injured. This is unacceptable.
“The policing operation will continue into the evening.”
The Met said earlier a section 35 dispersal order is in place for “a number of areas” across Westminster, including Parliament Square. The force said: “Officers are engaging with those in Parliament Square and will be advising them of this order.”
In a separate tweet, the Met said a crowd in Parliament Square had been “dangerously lighting fireworks and rockets”.
It added: “Some have struck people or exploded near to the crowd, this could cause very serious injury. We have moved into the crowd to remove any fireworks and prevent people [from] coming to harm.”
One participant, who gave his name only as Richard, from London, said the protest, which has taken place on 5 November for several years, was a “continuation” of the “anti-Covid” marches.
“It’s basically a continuation of the anti-Covid marches that we’ve been on since the beginning of the year,” he said. “It’s a couple of fingers in the direction of the establishment.”
Ahead of the demonstration, the Met said officers would work closely with protest groups to “ensure gatherings are safe and disorder is minimised”.
Last year, almost 200 people were arrested during the protest for breaching lockdown restrictions.