In a tweet on Saturday, Johnson said the protests had resulted in “shameful attacks on police in Bristol”.
“Our policemen shouldn’t have to face bricks, bottles and fireworks being thrown at them by a crowd with the intention of violating and causing damage to property,” he said.
People took to the streets on Friday night – the third protest in a week – to express their opposition to the bill, with more protests expected across the UK over the weekend.
Crowds walked through Bristol city center – past the site of the now-fallen statue of slave trader Edward Colston – and ended up outside Bridewell police station, where stones were thrown by protesters last weekend.
More than 1,000 people attended, according to the Avon and Somerset police, and protesters could be heard shouting “peaceful protest” and “shame” to the police.
Videos circulating online appear to show protesters being thrown to the ground and hit by anti-riot shields.
A Daily Mirror journalist tweeted a video of police officers apparently pushing him hard out of the way and apparently hitting him with truncheons, while he shouted, “I’m the press!”
Avon and Somerset police said they were aware of the video and were trying to contact the journalist involved.
Police said items such as eggs and cups were thrown at them, fireworks were launched in their mounted section and attempts were made to pull their shields. In total, 10 people were arrested, with dogs and horses being used by police officers until 1 am local time.
Superintendent Mark Runacres said that “most people acted peacefully, however, there was a minority that once again showed hostility towards officials”.
Tensions were especially high because the same police force admitted on Friday that last weekend’s reports – alleging that police officers were injured, including broken bones and a punctured lung in the demonstrators’ hands – were false.
“Fortunately, the injuries – although still serious – did not involve fractures or a punctured lung. We believe the information had been verified, but it was not, and although we are sorry for that, there was no intention to deceive,” Avon and Somerset Police said in an updated statement.
The proposed policing bill, along with the violent interruption of a vigil for a woman murdered earlier this month and the arrest of an acting police officer on suspicion of her murder, has placed relations between the British police and much of the public under heavy pressure.
Metropolitan Police Officer Wayne Couzens was charged with the kidnapping and murder of Sarah Everard, in a case that was intensely followed and led to a renewed national discussion about intimidation, harassment and violence against women.
But the police also became a target of anger when they moved to a peaceful vigil in Everard, south London, on March 13 and seemed to force women to fall, an approach that led to a review and scrutiny of pending legislation that it would increase its powers to dismantle mass protests and meetings in the future.
Rob Picheta contributed reporting.