Who is Luigi Mangione, suspect in UnitedHealthcare CEO murder?

Police have identified a 26-year-old Maryland man as the suspect in last week's assassination of UnitedHealthcare CEO Brian Thompson, who was shot from behind outside a New York City Hilton hotel hours before a shareholder conference Wednesday.

Luigi Nicholas Mangione was arrested in Altoona, Pennsylvania, Monday morning after witnesses spotted him and thought he matched the suspect on a wanted poster. Police responded to the location for reports of a person matching the description of the man wanted for questioning in Thompson's murder, but Altoona police said they initially took him into custody on unrelated charges.

High-level law enforcement sources told Fox News and Fox News Digital that he had a "ghost gun" similar to the suspected murder weapon, a suppressor and a fake ID in his possession when taken into custody. The Associated Press also reported he had writings critical of the healthcare industry.

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Mangione graduated from the elite Gilman School, a private high school in Baltimore, at the top of his class. Video of his graduation ceremony shows he delivered the commencement speech.

"He seemed like a smart kid, he was always doing the right thing, it seemed like," a former classmate told Fox News Digital Monday. "Wasn’t crazy."

He said the news came as a shock when he heard of the arrest. 

"It's not like he wasn’t outgoing, or introverted," he said. Nice kid, always had a smile on his face. Never really got the vibes of him being socially awkward. So that’s why I’m really surprised. I graduated in 2015; he graduated in 2016, It’s crazy how 10, nine years later, how people can change."

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Mangione went on to graduate from the University of Pennsylvania with bachelor and master's degrees in engineering and was part of the Eta Kappa Nu Honor Society for Electrical and Computer Engineering.

Mangione was active on social media, with accounts on X, Facebook and Instagram. Posts discussed a range of interests, including artificial intelligence and social commentary.

His criminal record includes a December 2023 misdemeanor case in Honolulu, Hawaii, for trespassing at the Nuuanu Pali Lookout.

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New York City Mayor Eric Adams said at a press conference Monday that "He matches the description of the identification we've been looking for" and that he is "in possession of several items that we believe will connect him to this incident." 

Fox News' Greg Norman contributed to this report.