Two police officers were seriously injured and at least two police vehicles were set on fire in the city of Bristol in southwest England during violent scenes on Sunday, police said.

Thousands of demonstrators had converged on the city center, ignoring COVID-19 restrictions, to protest against a government bill going through parliament that would give police new powers to restrict street protests.

Two officers were taken to hospital, one with a broken arm and another with broken ribs, while others were subjected to violence and verbal abuse. The outside of a police station in the city center was vandalized.

The local force, Avon and Somerset Police, said the demonstration began peacefully but later turned violent because of a small minority of protesters.

"All those involved in this criminal behavior will be identified and brought to justice. There will be significant consequences for behavior such as this," Avon and Somerset's chief superintendent, Will White, said in a statement.

Home Secretary Priti Patel said on Twitter that the scenes in Bristol were unacceptable.

"Thuggery and disorder by a minority will never be tolerated," she tweeted. "Our police officers put themselves in harm's way to protect us all. My thoughts this evening are with those police officers injured."

The government's Police, Crime, Sentencing and Courts bill would give police new powers to impose time and noise limits on street protests.

That has angered activists, particularly since a heavy-handed police response to a London vigil for murder victim Sarah Everard on March 13 caused widespread outrage and criticism of the police.

Although the bill pre-dated the Everard case, the timing of the bill was up for debate in parliament two days after the London vigil.

Some demonstrators carried placards with slogans such as "Kill the Bill," "The Day Democracy Became Dictatorship" and "We Can't Be Silenced That Easy."

(With input from Reuters)