Sunseekers have been urged to stay away from the beach when thousands flocked to the Dorset coast and a major incident was reported in Bournemouth.
Bournemouth Christchurch and the Poole Council said it “spread to the absolute hilt” on the second day of a UK heat wave.
Dorset police said there were reports of blocked roads, fighting and night camps.
People were urged to “act responsibly” as temperatures reach 20 years.
By mid-morning, Bournemouth Beach was busy “as far as the eye could see” and the Durdle Door parking lot was nearing capacity.
Traffic built up early on coastal roads and with people traveling to Bournemouth from as far away as Birmingham.
The council said declaring a major incident means “an emergency response has been triggered by multiple agencies to coordinate resources across the area to address the issues.”
Council leader Vikki Slade said: “We are absolutely horrified by the scenes witnessed on our beaches, particularly in Bournemouth and Sandbanks, in the past 24 to 48 hours.
“The irresponsible behavior and actions of so many people are simply shocking and our services stretch to the limit trying to keep everyone safe. Now we have had no choice but to declare a major incident and initiate an emergency response.”
The council confirmed that it had issued a record 558 parking tickets and said there was now an additional application.
He said that on Thursday morning, 33 tons of debris were cleaned along the coast, in addition to the eight tons collected between the docks on Wednesday.
East Bournemouth MP, Tobias Ellwood, said he had asked the government to send additional officers to Dorset if necessary.
“I have spoken to the police minister to tell him to be prepared, be prepared for the Dorset police to make that request, to say that they are inundated with traffic problems and antisocial behavior,” he said.
“It is very sad to see that several people are selfish and also act dangerously.”
Ellwood said it was “impractical” to close Dorset’s beaches entirely, but suggested warning signs of overcrowding at railway stations and oncoming freeways.
He added that the government should be “dynamic” in its response to people who flooded the beaches, otherwise the closure “would not have been at all.”
“I am sorry to see the departure of briefings # 10 because they would have been perfect for today – for a key figure at # 10 to clarify what is really happening in Bournemouth and to clarify that message at the national level – to say ‘please stop stay away from all our boardwalks for now, “he said.
Additional police patrols have been added and security measures have been put in place to protect crews from debris that the council said faced “widespread abuse and intimidation” when the containers were emptied.
Dorset Police Deputy Police Chief Sam de Reya said people should stay away from beaches in these “unprecedented times.”
“We also depend on people taking personal responsibility and we strongly recommend that members of the public think twice before heading to the area.”
“Clearly, we are still in a public health crisis and such a significant volume of people heading to an area puts increased pressure on emergency services resources,” he said.
The photos showed crowded beaches and beauty spots on Wednesday, which was the hottest day of the year in the UK so far.
David Morley, who lives in Sandbanks, said: “What we saw was a complete collapse of decent normal behavior and law and order, it is completely flooding the system.”
LIVE: Thousands of people flock to the beaches in a heat wave
The chain shuttle linking Sandbanks and Studland was unable to transport vehicles until Wednesday night due to stagnation on the surrounding roads. There were also reports of illegal overnight camps on Bournemouth beach.
Elsewhere on the coast, the police on the Hove Lawns boardwalk issued a dispersal order after a large meeting.
On the scene, Emily Hudson, BBC South
From Bournemouth Pier there are thousands of people as far as the eye can see. Some in the sea on inflatables, others sitting on the sand, there are important [numbers of] gazebos: there is a group of approximately 50 people.
A man told me that he camped in a tent overnight, many people have come from Birmingham, a six-hour round trip. People told me they wanted to “get out” after closing.
It is incredibly difficult to maintain social distance: people certainly cross each other within 2m.
A Birmingham woman admitted she was uncomfortable, but said: “You have to understand, after three months of confinement in the city center, even seeing the sea is worth it.”
Dorset Councilwoman Laura Miller said she was verbally abused and spat on while directing traffic to Durdle Door on Wednesday.
The roads to the beauty spot were closed after people were unable to use the pre-reservation parking system.
“Our local industry depends on tourism, we are not saying ‘don’t come’, but come in a safe and managed way. When you are too busy, nobody is having fun,” he said.
The parking lot was nearing capacity again mid-morning on Thursday.
Current government guidelines state that households can drive any distance in England to parks and beaches.
Earlier this month, both Dorset councils had asked the government to impose travel restrictions, raising concerns that the number of visitors could increase Covid-19 cases in the county.
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