LONDON — The hullabaloo began, as many do, with a tweet — when the assailant announced his deadly deed in a boastful post.

On Thursday, the day after Christmas, which is the jolly Boxing Day holiday here, the esteemed, brand-named British barrister Jolyon Maugham announced to the world, “I have killed a fox with a baseball bat.”

He added: “I was wearing a kimono.”

The story, naturally, took off on social media, then consumed the weekend newspapers in Britain, with pages and pages of commentary, continuing with radio talk shows on Monday.

Why? For starters, Maugham was a force and founder behind the Good Law Project, which mounted legal challenges to ­Brexit. The pro-Brexit tabloids had special fun hoisting Maugham on his own bat/petard.

The incident also spoke to the divide between town and country, between the urbanites who buy the organic eggs and the farm folk who kill the pigs and sheep that people eat.

And for some, it was about cluelessness and class — with the image of a top lawyer, a London toff, dressed in a woman’s satin robe, whacking a fox whose crime was wanting to eat a chicken.

Many Brits are rather fond of foxes.

In multiple after-tweets, Maugham elaborated that he awoke with a wee hangover — “slightly post-Xmas” — when he spied the fox, a big one, trapped in the netting he had arranged to protect his backyard chickens.

That’s when he donned his wife Claire’s green satin kimono and grabbed the bat, he said.

“I didn’t especially enjoy killing it but I imagine that’s what the RSPCA would have done, if they had anyone on call in Central London on Boxing Day,” he wrote.

Worth mentioning: Boxing Day was traditionally a big day for ye olde fox hunts, the ones with riders in red coats, chasing packs of baying dogs. Those have been banned.

Also worth mentioning: The RSPCA is the Royal Society for the Prevention of Cruelty to Animals, the oldest and largest animal welfare organization in the world and one of Britain’s largest charities, whose patron is Queen Elizabeth II. This is a country that takes animal welfare seriously.

In minutes after the barrister’s not-so-LOL tweets, posters began to express themselves, first with displeasure, then outrage, followed by petitions for Maugham’s arrest.

Nigel Evans, a Conservative Party lawmaker in Lancashire, told the Telegraph newspaper that the fox killing was “disgusting . . . beyond understanding. He should face the full force of the law.”

In the Guardian, under the headline “Jolyon Maugham QC was a hero to many. Then he beat a fox to death,” columnist Barbara Ellen wrote, “Keeping chickens in your garden is arguably the kind of affectation that makes people hate the ‘metropolitan elite’ but, if people wish to do so, they should at least make their enclosures fox-proof.”

People demanded to know: Why a bat? Why a kimono? Why not free the fox?

“Wasn’t a great deal of fun. Got caught up in the protective netting around the chickens and I wasn’t sure what else to do. Not looking forward to untangling it,” Maugham wrote.

“To be quite honest, although I don’t enjoy killing things, it does come with the territory if you’re a meat eater,” he argued.

He added that his chickens had been “very distressed” by the fox.

One gent suggested that a real farmer would never club a fox to death but would finish it off humanely with a bullet. “Not sure guns are a great idea in Central London,” Maugham answered.

After the RSPCA was tagged on Twitter, the organization responded, “This is distressing to hear,” and said it was looking into the episode.

A person with knowledge of the events, who spoke on the condition of anonymity because the investigation was ongoing, said the animal welfare group did appear at Maugham’s house to take a look, take photos and take the dead fox away for autopsy and disposal.

Maugham told The Washington Post that he was not commenting to the press but would probably offer a detailed statement later this week.

Terry Woods, a wildlife consultant with Fox-A-Gon, which offers “humane fox deterrence,” told the Guardian newspaper that if Maugham had called the RSPCA hotline, a fellow such as himself would have popped around, placed a covering over the fox’s eyes, freed him or her from the netting, and tootled off for a vet exam and a quick release.

Ominously, for Maugham, Britain’s 1996 Wild Mammals Protection Act, says it is illegal for “anyone to mutilate, kick, beat, nail or otherwise impale, stab, burn, stone, crush, drown, drag or asphyxiate any wild mammal with intent to inflict unnecessary suffering.”

But others online have noted that Maugham did not intend to cause any unnecessary suffering, and that swiftly killing a sick or dying animal is not uncommon in the countryside.

Jenny McCartney in the Times of London remembered the trauma of losing her own chickens to foxes when she was young. But she cautioned, “Foxes are hungrier and wilier than us and they’re willing to stay up all night, plotting. And, in the court of public opinion, foxes hold all the poetry: ferally, flamingly beautiful, half-dog, half-cat, with a rogue streak of mystery.”

Maugham eventually seemed to accept that he wasn’t going to win the public’s backing on this one. He began to apologize: “I was slightly shocked by the whole tooth-and-claw experience when I tweeted and that was what I was trying to convey. But my tweet, one of a number about keeping chickens in urban London, should have conveyed that better.”