The suspect in the high-profile killing of a health insurance CEO that has gripped the United States graduated from an Ivy League university, reportedly hails from a wealthy family, and wrote social media posts brimming with cerebral musings.
Luigi Mangione, 26, was thrust into the spotlight after police revealed he was their person of interest in the brutal murder of UnitedHealth CEO Brian Thompson last week in broad daylight in Manhattan in a case that laid bare deep frustration and anger with America's privatised medical system.
Mr Mangione was subsequently arrested and charged with murder in the targeted killing of Mr Thompson on the streets of New York, along with other violations.
Mr Mangione was charged in New York on suspicion of one count of murder, two counts of second-degree criminal possession of a weapon, one count of second-degree possession of a forged document and one count of third-degree possession of a weapon, according to online court documents.
News of his capture in Pennsylvania - following a tip from a McDonald's worker - triggered an explosion of online activity, with Mr Mangione quickly amassing new followers on social media as citizen sleuths and US media tried to understand who he is.
While some lauded him as a hero and lamented his arrest, others analysed his intellectual takes in search of ideological clues.
A photo on one of his social media accounts includes an X-ray of an apparently injured spine.
No explicit political affiliation has emerged.
Meanwhile, memes and jokes proliferated, many riffing on his first name and comparing him to the Mario Bros character Luigi, sometimes depicted in AI-altered images wielding a gun or holding a Big Mac.
"Godspeed. Please know that we all hear you," wrote one user on Facebook.
"I want to donate to your defense fund," added another.
According to Mr Mangione's LinkedIn profile, he is employed as a data engineer at TrueCar, a California-based online auto marketplace.
A company spokesperson said Mr Mangione "has not been an employee of our company since 2023".
Although he had been living in Hawaii ahead of the killing, he originally hails from Towson, Maryland, near Baltimore.
He comes from a prominent and wealthy Italian-American family, according to the Baltimore Banner.
The family owns local businesses, including the Hayfields Country Club, its website says.
'A normal guy, nice kid', says former acquaintance
A standout student, Mr Mangione graduated at the top of his high school class in 2016.
In an interview with his local paper at the time, he praised his teachers for fostering a passion for learning beyond grades and encouraging intellectual curiosity.
A former student who knew Mr Mangione at the Gilman School said the suspect struck him as "a normal guy, nice kid".
"There was nothing about him that was off, at least from my perception," this person said, asking that their name not be used.
"Seemed to just be smiling, and kind of seemed like he was a smart kid. Ended up being valedictorian, which confirmed that," the former student said.
Mr Mangione went on to attend the prestigious University of Pennsylvania, where he completed both a bachelor's and master's degree in computer science by 2020, according to a university spokesperson.
While at Penn, Mr Mangione co-led a group of 60 undergraduates who collaborated on video game projects, as noted in a now-deleted university webpage, archived on the Wayback Machine.
Social media posts come under scrutiny
On Instagram, where his following has skyrocketed from hundreds to tens of thousands, Mr Mangione shared snapshots of his travels in Mexico, Puerto Rico and Hawaii.
He also posted shirtless photos flaunting a six-pack and appeared in celebratory posts with fellow members of the Phi Kappa Psi fraternity.
However, it is on X that users have scoured Mr Mangione's posts for potential motives.
His header photo - an X-ray of a spine with bolts - remains cryptic, with no public explanation.
Finding a coherent political ideology has also proved elusive, though he had written a review of Ted Kaczynski's manifesto on the online site goodreads, calling it "prescient."
Kaczynski, known as the Unabomber, carried out a string of bombings in the United States from 1978 to 1995, a campaign he said was aimed at halting the advance of modern society and technology.
Mr Mangione called Kaczynski "rightfully imprisoned," while also saying "'violence never solved anything' is a statement uttered by cowards and predators".
According to CNN, handwritten documents recovered when Mr Mangione was arrested included the phrase "these parasites had it coming".
Mr Mangione has also linked approvingly to posts criticising secularism as a harmful consequence of Christianity's decline.
In April, he wrote, "Horror vacui (nature abhors a vacuum)".
The following month, he posted an essay he wrote in high school titled "How Christianity Prospered by Appealing to the Lower Classes of Ancient Rome".
