More from witnesses here: people packed on to the street to watch the Liverpool FC parade were only alerted to the danger by screams from the crowd, one said.

The woman, who gave her name as Chelsea, told BBC Radio that enabled some people to jump out of the way as the driver showed no sign of slowing.

“With the commotion, that was the only reason we looked up, and thankfully, looked up and managed to jump out [of] the way in time,” she said.

Reuters also reports another witness as saying before the incident that there was disorder in the city centre where the parade was due to pass, with overcrowding and spectators confused by a lack of signage about street closures or where they should go.

Liverpool last won the trophy during the Covid pandemic when celebrations were not permitted due to lockdowns.

Politicians in Britain and in Ireland, where the club is popular, thanked emergency services. “My thoughts are with all those injured or affected,” Keir Starmer, the prime minister, said on X, calling the scenes appalling and saying he was being updated.

Liverpool FC said on X it was in direct contact with police:

Our thoughts and prayers are with those who have been affected by this serious incident.

Just to recap, with most people off work for the spring bank holiday, hundreds of thousands of fans had gathered to watch the Liverpool team and its staff travel through the city centre on an open-top bus with the Premier League trophy.

Videos on social media showed people thrown into the air as the car rammed into spectators, Reuters reports. When the car stopped, angry fans converged on it and began smashing the windows as police officers intervened to prevent them from reaching the driver.

In the aftermath, emergency services were seen carrying victims on stretchers to ambulances and debris scattered on the road.

The incident “cast a very dark shadow over what had been a joyous day”, Liverpool city council leader Liam Robinson said on social media.

Police were unusually quick to give a description of the man they arrested. Dal Babu, a former chief superintendent in London’s Metropolitan Police, told the BBC this was an effort to cool social media speculation that the episode was an Islamist attack.

The same police force oversaw the response to the murder of three young girls in the nearby town of Southport last year, an incident which sparked days of rioting, sparked by speculation online over the identity of the attacker.

The former Labour shadow chancellor John McDonnell has expressed his solidarity with the people of Liverpool.

The independent MP posted on X:

It’s hard to put into words our feelings about the terrible events in Liverpool today. For a wonderful day of joy to be turned into one of horror is an absolute tragedy. All of those hurt are in my thoughts. As always Liverpool will stand together in solidarity. YNWA

The independent MP Apsana Begum has hailed Liverpudlians’ “exceptional strength” in times of adversity.

She tweeted that she was thinking of all those affected by what happened, also saying on X:

The people of Liverpool have always demonstrated exceptional strength and unity in times of adversity. We stand with you in solidarity.

Former Liverpool manager Sir Kenny Dalglish, who was at the parade, has said he is “shocked, horrified and deeply saddened about what happened at the end of the parade today.”

In a post on X he said:

Our anthem has never felt more appropriate, You’ll never walk alone. Your Liverpool family are behind you.

Everton, Liverpool’s Merseyside rivals, have said “Our thoughts are with all those who have been affected by this serious incident in our city.”

Paddy Edrich, a reporter with the Liverpool Echo, has shared this image of the aftermath:

Andy Hunter, our Merseyside football correspondent, has written about how a day of celebration turned into one of horror.

The Strand had been a scene of sheer euphoria 25 minutes earlier.

At 5.41pm the open-top bus parading the Liverpool team had passed by the Royal Liver Building and a huge crowd broke into a powerful rendition of You’ll Never Walk Alone to celebrate the new Premier League champions.

Fireworks and ticker-tape exploded overhead. From an apartment on Mann Island, former Liverpool managers Jürgen Klopp and Sir Kenny Dalglish waved to jubilant supporters below.

Just after 6pm, on nearby Water Street, the scene was one of devastation. A car, driven by a 53-year-old white British male from the Liverpool area, collided with a number of pedestrians including four children.

Twenty-seven people were taken to hospital, with two sustaining serious injuries, including one of the children.

Another 20 were treated for minor injuries at the scene and others self-presented at hospitals on Merseyside later in the day.

Ambulances were parked outside Liverpool town hall over three hours later.

Approximately 20 to 30 casualties were being treated in the Riva Italian restaurant across the road.

One man from Birmingham, who asked not to be named, had been treated for back and leg injuries having been knocked over in the incident.

Our north of England editor, Josh Halliday, was at the press conference tonight, here is his write-up:

Four children were injured, including one critically, when a car ploughed into fans at a Liverpool football victory parade in an incident not being treated as terror-related, authorities said.

One of the children suffered “major injuries” in the “horrific” collision that caused dozens of casualties just after 6pm on Monday.

At a press conference in the Cunard building in Liverpool on Monday might, North West ambulance service (NWAS) said 27 patients were taken to hospitals around the city – including two who sustained major injuries. One of those is a child.

NWAS said 20 other people were treated for injuries at the scene and that other people were still arriving at hospital seeking treatment.

Jenny Sims, the assistant chief constable of Merseyside police, urged people not to share misinformation about the incident and said it was not being treated as terror-related.

She said: “What I can tell you is that we believe this to be an isolated incident and we are not currently looking for anyone else in connection with it. The incident is not being treated as terrorism.”

The press conference has come to an end. Simms said the incident is not being treated as terrorism and that police are not currently looking for anybody else in relation to it.

Kitchen said four of the people injured were children. He said 20 people were treated for minor injuries at the scene and 27 were taken to hospital.

Two of them, including one child, are thought to have sustained serious injuries.

No fatalities have been reported.

Shadow home secretary Chris Philp has also commented on the incident.

He ended a post on X with the line: “The public deserve to know the full facts as quickly as possible”, which has drawn some ire.

Khayer Chowdhury, a Labour councillor in Redbridge, east London replied: “A disgusting tweet from a nasty party that is now rightfully heading straight into history’s dustbin. Have some self-respect and dignity you opportunistic, rancid idiot.”

Earlier this evening, Merseyside police and crime commissioner, Emily Spurrell, urged people not to speculate about the incident.

23 minutes after Philp’s tweet, Merseyside police released more information about the incident, including confirming that “the man arrested is a 53-year-old white British man from the Liverpool area”.

Liam Robinson, leader of Liverpool city council is now speaking. He said: “I’d like to start by saying, on behalf of everyone here in Liverpool, how much our thoughts and prayers are with those affected by this appalling incident in the city center.

“Today has cast a very dark shadow of what had been a joyous day for the city and the finale to a fabulous bank holiday weekend. I’d particularly like to pay tribute to the emergency services who responded to help those who were hurt, and to our NHS staff treating them in hospital.

“We are working very closely with Merseyside police to support their investigation and with other relevant organisations to make sure those affected get the appropriate support.

“I would appeal for people please do not share the horrifying footage of the incident on social media. If you have any information, forward it to Merseyside police to help them with their investigation. We won’t be commenting any further, but we will provide relevant updates as and when we know more and it’s appropriate to do so.”

Nick Searle, the chief fire officer is speaking now. He said: “This evening, Merseyside Fire and Rescue Service were informed at 18:07 hours and we immediately mobilised three fire engines to Water Street and were in attendance in four minutes on arrival.

“The crews were met with numerous injured people and four persons trapped under a vehicle. Our crews rapidly lifted the vehicle removed three adults and one child from beneath and passed them to our ambulance service colleagues.”

Dave Kitchen, from the North West ambulance service is now speaking. He said he was “horrified and saddened that a day of celebration for the people of Liverpool could end in such terrible circumstances”.

Simms said the 53-year-old white British man is believed to be driver of the car.

She said: “The car stopped at the scene and a 53-year-old white British man from the Liverpool area was arrested, we believe him to be the driver of the vehicle.

“Extensive inquiries are ongoing to establish the circumstances leading up to the collision, and it is vital that people do not speculate or spread misinformation on social media.”

The press conference has now begun. Assistant chief constable Jenny Simms is speaking.

“My thoughts are with all those injured in tonight’s horrific incident, their family and friends and all of those affected by the terrible tragedy that has taken place today.

“I want to thank all of the emergency services partner agencies and members of the public who came to the assistance of the injured following this evening’s shocking incidents, which we declared a major incident.

“This had been a joyous day in Liverpool, with hundreds of thousands of people lining the streets to celebrate Liverpool football club’s victory parade. Sadly, at six o’clock this evening, as the parade was drawing to a close, we received reports that a car had been in a collision with a number of pedestrians on Water Street in Liverpool city centre.”

The British health secretary, Wes Streeting, has posted on social media about the “horrible incident” in Liverpool.

“I would like to thank our amazing emergency services for their heroic actions this evening in Liverpool,” he posted on X, formerly Twitter.

He added: “My heart goes out to everyone impacted in this horrible incident.”

Streeting finished his post by saying, about the National Health Service: “My Department is working with NHS England to keep across any developments for our NHS staff.”

Our north of England editor, Josh Halliday, has spoken to another witness.

Les Winsper, 55, witnessed the incident unfold right in front of him.

“People started banging on the [car] windows,” he said. “Then they smashed the windows and he panicked and put his foot down. He then hit someone and that person has gone in the air and he’s ploughed through the rest of them. I’ve never seen anything like it.”

Winsper’s friend, Craig Steward, 52, said there was “chaos” with “people crying, children crying, shaking”

Both men said the incident lasted 20 to 30 seconds.

Winsper said the first victim was thrown “about 20 feet” in the air by the collision.

He added: “I personally think he’s hit someone by mistake … and then he’s put his foot down … It was the worst thing I’ve seen in my life, you see it on TV. That’s why all the kids are crying because they witnessed it … I’m traumatised”.

Simon Harris, the tánaiste (deputy prime minister of Ireland), has said the country’s “thoughts are with the people of Liverpool this evening”.

“This was supposed to be a night of celebration for this city and Liverpool fans.

“Instead we are witnessing some devastating scenes unfold.

“My officials in the Department of Foreign Affairs and Trade are keeping me up to date with developments.

NHS University Hospitals Liverpool Group, which operates four hospitals in the area, has urged members of the public to refrain from calling to ask about loved ones because next of kin would be contacted.

In a statement the trust said: “Following the incident in Liverpool city centre this evening, we know that many people are concerned about loved ones.

“Next of kin will be contacted, so please help us to manage the incident as best we can by refraining from calling our switchboard.”

Some updates on those being treated inside the Riva restaurant, which took in people affected by the incident.

Andy Hunter, our Merseyside football correspondent, reports that two people have been taken out of the restaurant on stretchers and put in ambulances in the last 30 minutes. Both were sat upright and were talking to medics.

Josh Halliday, our north of England editor who is on the scene, said it is understood that about 30 people were treated for injuries or shock in the Riva restaurant, which is opposite Liverpool town hall, around the corner from the scene of the collision.

More political reaction is coming in.

Kemi Badenoch, leader of the Conservative party, said: “The pictures emerging from Liverpool are deeply worrying. My thoughts are with all those affected, and the emergency services as they respond to what appears a horrific incident.”

Nigel Farage, leader of Reform UK, said: “Horrified to see the scenes in Liverpool. My thoughts are with all of those affected and injured by this disturbing attack.”

Our Merseyside football correspondent, Andy Hunter, is on the scene.

He is reporting that emergency services are still on the scene on Water Street, with casualties being treated in the Riva restaurant nearby.

Outside the police cordon, Sonny Singh, 40, said he saw an injured teenager and dozens of people run past him “crying and angry” shortly after the collision.

“People were running, screaming … I saw a boy, probably about 15, holding his leg and bleeding. There were loads of people there,” he said, adding that he had heard the vehicle hit dozens of fans.

Singh, from Leicester, had been celebrating with his two sons, aged nine and 13, when the incident unfolded shortly after 6pm.

Local restaurants are reportedly opening their doors to treat those in medical need.

Paddy Edrich, a reporter at the Liverpool Post, said on X that people are being given medical attention inside a nearby Italian restaurant.

“People inside Riva are being treated by paramedics. Some have bandages around their heads and limbs. Staff in the restaurant appear to be providing fluids to those being treated and the emergency services.”

The Merseyside police and crime commissioner, Emily Spurrell, has urged people not to speculate about the incident.

She said: “The footage from tonight’s parade is shocking and appalling. My thoughts are with all those affected.

“A 53-year-old white British male from the Liverpool area has now been arrested.

“My thanks go to Merseyside police and our emergency service partners who have responded so swiftly.

“Updates will be provided as soon as possible. In the meantime, I’d urge people to please not speculate any further.”

One eyewitness said the vehicle reversed before “what seemed like an incredibly deliberate” acceleration into a crowd of people near the packed Water Street area of the city centre.

Footage appears to show the car hit a number of people before being surrounded by a crowd who apprehended the driver.

It is understood that St John Ambulance personnel were among the first at the scene to treat those injured, some of whom are believed to be in a critical condition. A reporter at the scene saw two “distressed” volunteer medics being comforted by colleagues as they made their way from the scene.

Steve Rotheram, mayor of the Liverpool city region, has thanked first responders for their “swift action” on a “difficult day”.

He said: “Our hearts go out to all of those affected, especially those who have been injured. Thank you, as ever, to the first responders for their professionalism and swift action.

“This is a difficult day for our city region, but we stand together.”

PA has words from another eyewitness. Peter Jones, 44, from the Isle of Man, attended the parade and described the incident as “shocking”.

He said: “We were walking up Water Street, thousands around us.

“We heard a frantic beeping ahead, a car flew past me and my mate, people were chasing it and trying to stop him, windows smashed at the back.

“He then drove into people, police and medics ran past us, and people were being treated on the side of the road.

“There were a lot injured. We heard it behind us hit the crowds, then we saw half a dozen people [injured] in the road as we were walking up.

“It was shocking. We’re back at our hotel now, in a bit of a shock.”

The Premier League has said it is “shocked” by the incident in a post on X.

It read: “Everyone at the Premier League is shocked by the appalling events in Liverpool this evening, and our heartfelt thoughts go out to all those injured and affected.

“We have been in contact with Liverpool FC and have offered our full support following this serious incident.”

BBC reporter Matt Cole witnessed the incident while attending the parade with his family.

He told BBC News: “I was there with my family. We had just moments before watched fireworks going off and celebrations, the Liverpool bus passing us on the Strand.

“There were screams ahead of us and suddenly this dark blue car just came through the crowd.

“It just wasn’t stopping. I managed to grab my daughter who was with me and jump out of the way.

“It missed myself and my family by literally inches. We then turned and watched what happened momentarily behind us before running.

“It was being chased by a group of men who were trying to bang on the side of it and throw things at it.

“The back of the rear windshield had been completely smashed in, but it just had no intention of stopping.

“At that point, we and others dived into a sidestreet and then once I was sure my family were safe, I looked back to see people sitting on the ground surrounded by people.”

Liverpool FC has issued a statement on the incident.

A spokesperson for the club said: “We are in direct contact with Merseyside police regarding the incident on Water Street which happened towards the end of the trophy parade earlier this evening.

“Our thoughts and prayers are with those who been affected by this serious incident. We will continue to offer our full support to the emergency services and local authorities who are dealing with this incident.”