Six people were arrested and several police officers were injured during violent protests in Plymouth city centre, police have said.

Two groups of protesters clashed on Royal Parade and outside the Guildhall on Monday evening in the latest of a series of incidents across the UK following the killing of three girls in Southport, Merseyside, on 29 July.

Devon and Cornwall Police said people intent on committing public order or criminal offences were dealt with “robustly” with six arrests made.

The force said some officers sustained minor injuries, while two members of the public were taken to hospital to be treated for injuries.

A police statement said: “Violence will not be tolerated, hate will not be tolerated, and we will continue to work with our partners to keep the people of Devon, Cornwall, and the Isles of Scilly safe and reduce anti-social behaviour.”

The force issued an appeal for witnesses, including anyone who has video or photographs, following the protests.

The force added its “approach to this operation was to enable peaceful protests, but people who were intent on committing public order or criminal offences, have and will be dealt with robustly”.

Clashes broke out between the groups, which consisted of anti-immigration protesters on one side of Royal Parade, which separates the city from the Hoe and waterfront, and a counter demonstration on the other.

A police van was also damaged during the protests.

Devon and Cornwall Police and Crime Commissioner Alison Hernandez said officers were called in from neighbouring forces including Avon and Somerset, Wiltshire and Dorset to help.

She said bricks and fireworks were thrown at police but there were no serious injuries.

“The violence we saw last night is completely unacceptable,” she said.

“I would like to pay tribute to the frontline officers who put the public’s wellbeing ahead of their own in order to gain control of the situation, and in doing so were hurt in the line of duty.”

Jemima Laing, Plymouth City Council’s deputy leader, said the authority would start assessing any damage caused and repairs required on Tuesday morning.

Ms Laing said: “I remain incredibly angry on behalf of Plymouth that so many people from outside our city felt emboldened to come here and cause disruption and unrest.

“Thuggery on tour is not acceptable.”

Reporting from Royal Parade, BBC Radio Devon’s Hattie McCann said the clean-up operation had already started.

“Standing here on the plaza on the Royal Parade, you would never know anything has happened,” she said.

“There are a couple of broken bottles and lots of street cleaners – and Plymouth City Council are out in full force.”

Plymouth City Council said streets had been “strewn with debris from rocks and glass bottles together with small paving stones which had been ripped from the ground”.

There were also a number of damaged bins including a burnt out bin on the Hoe and rubbish left strewn near Tinside.

Councillor Sally Haydon, cabinet member for community safety, said it was thanks to council workers’ “magnificent efforts” that Plymouth was “again looking spic and span”.

She said: “I know that last night has left city centre businesses shaken, but we would like to thank them for taking precautions by closing early and working with the police and the council to minimise the potential for damage.

“And the message to our residents – the city centre is safe! Please show your support by popping down, spending time there, being part of the heart of Plymouth.”

Plymouth Citybus said it was unable to serve routes along Royal Parade until 06:45 BST on Tuesday.

The bus firm said on X: “Please be patient as things take a little time to return to normal operation.”

In a second tweet, Citybus thanked passengers for their patience and urged people to “be kind” to each other.

Several businesses in and around the Royal Parade area, including the Theatre Royal Plymouth, which cancelled its scheduled performance of The Devil Wears Prada musical, closed early on Monday ahead of the protests.

Josh Thomas, who lives on the Hoe, said hundreds of people ended up by the war memorial later in the evening

He said at one point, a fire was set by the war memorial before a group of about 100 protesters went down the street he lives on and attacked a car.

“There’s no clear message, there’s nothing to gain from what went on, it was kind of a bit mindless,” Mr Thomas said.

The Right Reverend James Grier, the Bishop of Plymouth, said it was time for people to help bring calm back in the city.

“There are consequences and justice needs to be done and actions need to be taken,” he said.

“But that’s not down to us, the normal people, our job is to speak peace and love and community rather than propagate aggression and violence.”