Thousands of people have headed to English beaches, with many apparently unconcerned about public health issues.
"Hundreds die every day yet people think it's OK to have a jolly on the beach," a walker in Southend said.
Norfolk Chief Constable Simon Bailey said he feared there was a perception that lockdown was "done and dusted".
Mr Bailey said some parts of Norfolk had seen numbers typical of a regular summer bank holiday and he was concerned at the "lack of respect" for communities who had "done their best to protect themselves".
"We're dealing with far more people heading to the coast, and with the beautiful weather we're having that's not surprising," he added.
"What I do find surprising is a sense that lockdown has been lifted, we can do what we want and the coronavirus challenge has passed.
"I'm really concerned. That is simply not the case."
In Newquay, Cornwall, police said they moved on camper vans that had stayed overnight, while in Bournemouth the borough council urged people to go home if the beach looked too busy.
Mark Husmann, who did a beach litter-pick at Tynemouth, North Tyneside, said: "I'm pretty horrified.
"There were masses of people on the beach who seem to think that a global pandemic is less serious in the sunshine."
His Facebook post was echoed by Cathy Kent, who said after seven "glorious" weeks of a litter-free, empty beach at Exmouth in south Devon, the past 10 days had been far busier, with discarded glass bottles a regular find.
In Southsea, Hampshire, Tania Simmons said every bin on her beach walk on Thursday was was "overflowing with rubbish, beer bottles and barbecues", with broken bottles left on the promenade and rubbish strewn across the common.
"It's bloody disgraceful," she added.
Visit Blackpool recently rebranded as "Do Not Visit Blackpool" to discourage visitors as lockdown restrictions were eased.
Hotelier Lyndsay Fieldsend said she had seen a "surge of day-trippers" since then and beaches full of litter.
Council leaders in Sussex, including in Hastings and Brighton, have said the area's amenities are not open to visitors, although Dorset Council said it would reopen some car parks and public toilets in key locations in time for the bank holiday weekend to help cope with demand.
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