LONDON — Like refugees fleeing a coming contagion, anxious, stir-crazy Brits poured out of the cities and into the countryside over recent days, to postcard-perfect hamlets and wind-swept islands, seeking solace or safety in the mountains, lakes and shore. 

They were not welcome. The emphatic message from the locals: Go away.

Jittery urbanites drove their camper vans up to the Scottish Highlands, and the worried well searched for holiday cottages to self-isolate in Cornwall.

With international jet travel nearly shut down, schools closed and London the germy epicenter of infection in Britain, the people were hitting the highways and boarding trains to the boonies.

But out in the countryside, locals warned outsiders, essentially, “You’re going to kill us.” Some of the prettiest places in England, Wales and Scotland are also the least populated and the most underserved by the National Health Service.

On Monday night, frustrated with the public’s refusal to abide by calls to practice strict social distancing measures — and fearing that a coming wave of coronavirus patients could soon overwhelm hospitals — Prime Minister Boris Johnson issued new edicts: People were ordered to stay at home, except to go shopping or visit the doctor or pharmacist. They will be permitted a bit of daily exercise. They were told not to travel — except to go to work, to do jobs they cannot do from home.

The tabloids have adopted a new term for those who fail to practice proper social distancing, who hoard food and travel to moors and lochs to hide out.

“Beauty spots beg ‘covidiots’ to stay away,” went the Daily Mail headline.

Angus MacNeil, a member of parliament from the Hebrides, the archipelago of islands off the northwest coast of Scotland, posted photos of his home island of Barra that features the Castlebay Village Hall with a short row of empty cots awaiting patients.

“This is not far from 3rd world basic,” MacNeil tweeted. “No ventilators, no much oxygen either, no testing. Islands such as this could be badly hit. Message is don’t come on holiday please.”

Lawmakers in Parliament on Monday denounced “self-isolation holidays.”

Ian Blackford, leader of the Scottish National Party in Westminster, said, “I have more than 1,000 emails over the weekend from constituents, petrified with what’s going on.” He said outsiders were flocking to areas in the Scottish Highlands that are “more than three hours from Inverness,” which has only one hospital to offer acute care.

“This is a dangerous, dangerous situation that’s imperiling the lives of our constituents. Tourists must go home and must stay at home,” he said.

Whether the new measures announced Monday night will stop holidaymakers fleeing to the countryside to escape the virus is unknown.

Johnson said the police will have the power to break up public gatherings and could issue fines. But there is no plan to stop and check cars heading out of the cities.

On Monday, the United Kingdom had nearly 6,000 confirmed cases of coronavirus, with 335 deaths. Late Monday, British Prime Minister Boris Johnson ordered all citizens to stay home. He said all nonessential shops will close, travel will be restricted, and police will enforce social distancing if necessary.

The glorious mountains of Snowdonia National Park in Wales saw traffic jams on Sunday, with overflowing car parks and a mile of vehicles parked along the verge.

The Welsh tourism board tweeted, “Visit Wales. Later.”

They begged outsiders, “Please do not visit Wales at this time and avoid all unnecessary travel within Wales.”

Even in the best of holiday seasons, the people of Cornwall in southwest England have a love-hate relationship with the hordes of summer visitors the locals call “emmets,” which is Cornish for ants.

Jess Earle of Portwrinkle Holidays in Cornwall told the BBC he had received death threats after offering holiday flats for people to self-isolate.

“The idea is to allow families with elderly relatives to come down here and ride this out at winter rates,” he said. “We are very secluded and we’ve had a lot of interest. But I’ve had a lot of stick about bringing disease into the country, which is very sad.”

The police in the scenic Lake District in northwest England declared the county was “no longer conducting business as usual.” With pubs and restaurants closed, corona-tourists could overwhelm scant local services.

The Mail in Cumbria quoted a local farmer from Langdale, Jonathan Benson: “Car parks are full, they are parking along the road sides.”

Benson warned, “Businesses will find it hard for a month and I understand a lot of my friends rely on tourism. But people will lose loved ones if we don’t get on top of this.”

Some of Britain’s national parks saw their busiest days — ever — over the weekend.

The National Trust and the Royal Horticultural Society announced that they were closing all their historical manors and elaborate gardens as they could no longer guarantee the safety of visitors.

In London’s parks, football pitches, marshlands and heaths, a lot of people appeared to have suddenly taken up jogging.

The prime minister, himself a bicyclist, lamented Sunday night that open spaces were vital to the public’s mental health during this crisis, but that the people were not heeding the simplest of warnings: to maintain strict social distancing by keeping two meters, about six feet, from each other.

Public health officials were dismayed to see the images from news outlets on Sunday that showed people packed into the parks, gathering in large groups, with ramblers jostling with kids in strollers beside elderly couples walking arm-in-arm.

The Royal Parks of Regent’s, Hyde and St. James’ were like a petri dish, with benches and daffodils.

“It’s very selfish,” Health Secretary Matt Hancock told the BBC on Monday. “If people go within two meters of others who they don’t live with then they’re helping to spread the virus — and the consequences of that costs lives and it means that, for everyone, this will go on for longer.”