Talia Jane Men in hoodies in a park in New York CityTalia Jane

They came in hoodies, they came in masks, shuffling their feet and laughing nervously while waiting for a winner to be announced.

Just a few days after UnitedHealthcare CEO Brian Thompson was murdered on a New York City sidewalk, these young men had lined up in Washington Square Park to compete in a lookalike contest for the man wanted for his murder.

It was sparsely attended and seen as a joke by those who did turn up, said Talia Jane, a journalist who was there.

But it underlined an obsession with a murder suspect that has gripped social media since the killing on 4 December, fuelled by latent anger directed at America's private health insurers.

"There was a lot of tinder already there, a lot of discontent, a lot of frustration already there, and [this] sort of threw a match on it," Ms Jane said.

And it has only grown since the suspect was named as Luigi Mangione, a 26-year-old Ivy League-educated member of a prominent Baltimore family.

In TikTok videos, memes and group chats, a young man accused of shooting a father-of-two in the back on a New York City sidewalk has been fawned over and praised as a kind of folk hero.

This fetishisation was remarkably widespread, not limited to radical corners of the internet or any political affiliation, troubling many observers.

"We do not kill people in cold blood to resolve policy differences or express a viewpoint," said Josh Shapiro, the governor of Pennsylvania, where Mr Mangione was arrested at a McDonald's. 

"In a civil society, we are all less safe when ideologues engage in vigilante justice."

Etsy was flooded with pro-Mangione apparel, while Amazon pulled similar products from their site. 

The McDonald's worker alleged to have turned him in has become a target for online hate, while the fast-food franchise itself has been spammed with bad reviews. 

The police department in Altoona, Pennsylvania, that arrested him even received death threats.

Much of this online reaction has focused on his looks, with the internet dubbing him the "hot assassin".

Indeed, Mr Mangione's appearance, which he showed off in shirtless social media posts, is now clearly part of the appeal, said cultural critic Blakely Thornton.

Americans are effectively "programmed" to trust and empathise with men who look like Mr Mangione, he said. 

"That's why they are the protagonists in our movies, books and stories."

Public adoration for handsome men accused of crimes is not new - from Ted Bundy to Jeremy Meeks, violent men have developed cult followings. 

But Professor Tanya Horeck, an expert on digital culture and true crime from Anglia Ruskin University, says that social media has given those sentiments massive visibility, and helped them spread.

The internet has caused "a blurring of the lines between celebrity and criminality", she told the BBC, adding that when people see a good-looking person pop into their feeds, their first thought is lust, not moral criticism. 

"The mood around Luigi Mangione is 'thirst'," she said.

Beyond his appearance, a large part of Mr Mangione's online appeal is clearly his apparent ire against the private healthcare industry and corporate elites in general. US media has reported that Mr Mangione was arrested carrying a handwritten document that said "these parasites had it coming".

The Network Contagion Research Institute (NCRI), a non-profit extremism research group based in New Jersey, said that after the shooting the hashtag #EatTheRich went viral.

Since Mr Mangione's arrest, variations of "#FreeLuigi" were posted on X over 50,000 times, likely getting tens of millions of impressions. And by some measures, the NCRI said, engagement with posts about Mr Thompson's killing across platforms like X, Reddit, and others surpassed that of the assassination attempt against Donald Trump in July.

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