An individual at a McDonald's recognized him from the wildly circulated images of the suspect sought in the shooting.
Mangione, 26, has been charged with murder in the shooting outside a Midtown Manhattan hotel ahead of an investor conference on December 4, according to the NYPD.
Mangione faces charges in New York and Pennsylvania
Mangione faces second-degree murder, possession of a loaded firearm, possession of a forged instrument and criminal possession of a weapon charges in New York.
The forged instrument is the fake New Jersey driver's license he allegedly used to check into the hostel on the Upper West Side.
Mangione remains in the custody of the Pennsylvania Department of Corrections without bail as he contests extradition to New York.
Mangione's Past
He has no prior arrest history in New York, NYPD Chief of Detectives Joseph Kenny said at a news briefing on Monday. Family and friends reacted with disbelief to his arrest.
The Mangione family released a statement saying, "Our family is shocked and devastated by Luigi's arrest. We offer our prayers to the family of Brian Thompson and we ask people to pray for all involved. We are devastated by this news."
His family says they "had lost touch" with him. His mother filed a missing persons report on November 18. The report was filed in San Francisco, according to two law enforcement sources.
Repeated requests for information about the report went unanswered by the San Francisco Police Department. Both the chief and the spokesman referred questions to the NYPD.
Mangione was born and raised in the Baltimore suburbs of Maryland. He attended the Gilman School, a private all-boys school in Baltimore.
Mangione was Gilman's valedictorian the year he graduated, 2016, and gave a speech at commencement in which he credited his classmates for their "inventive, pioneering mentality that accompanies a strong commitment to Gilman tradition."
Mangione thanked the graduates' families for their time and love, and every Gilman teacher in all three divisions.
"Our imagination draws from your inspiration, and our courage largely depends on your encouragement in the classroom, on the field, and on the stage," he said.
In a statement from a high school friend who spoke with ABC News, he said Mangione is "the last person I expected to be involved in something like this."
"He was an incredibly intelligent, humble, and kind person," said the classmate who graduated with Mangione in 2016. "He didn't give any indication of radical views or mental instability at the time. He seemed a like a very bright guy with a bright future."
Mangione is also a graduate of the University of Pennsylvania in Philadelphia. He majored in computer science and graduated in May 2020.
About six months ago, the classmate said he heard from other classmates that Mangione's family was "inquiring about his whereabouts."
"I heard that he got back surgery so we were all a little worried and many people reached out to him. No response," the classmate said. "I didn't hear anything about him until today when all the news dropped."
Following his graduation, Mangione worked as a data engineer at online car marketplace TrueCar, Inc. beginning in November 2020, according to a LinkedIn account that appears to belong to Mangione.
A representative for TrueCar said that Mangione stopped working for TrueCar in 2023.
Mangione's last known address was in Honolulu, police said. R.J. Martin, the founder of a co-living space for remote workers in Honolulu who said he was Mangione's roommate there, said he was "beyond shocked" by the news.
"It's unimaginable," Martin told Honolulu ABC affiliate KITV.
"Never once talked about guns, never once talked about violence," Martin told the station. "He was absolutely a not violent person, as far as I could tell."
Martin also recalled that Mangione had a back injury after a surf lesson and needed surgery.
He said they would talk about issues like health care, housing and food systems but "it wasn't anything specific."
"It wasn't like he had an ax to grind," he said.
Mangione's Writings
Mangione had several handwritten pages on him when arrested that appeared to express a "disdain for corporate America" and to indicate "he's frustrated with the health care system in the United States," NYPD Chief of Detective Joe Kenny told ABC News' "Good Morning America" on Tuesday.
The writings discovered by police read in part, "I'll keep this short, because I do respect what you do for our country.... Frankly, these parasites simply had it coming. A reminder: the US has the #1 most expensive healthcare system in the world, yet we rank roughly #42 in life expectancy."
Mangione considered the killing of Thompson to be a "symbolic takedown" of UnitedHealthcare over perceived corruption, according to a confidential assessment of the crime by the NYPD intelligence bureau described to ABC News. The assessment is based in part on the suspect's writings.
It is unknown if Mangione has a personal connection to UnitedHealthcare, NYPD Commissioner Jessica Tisch said.
Photos Released in the Case
NYPD officials released new images this weekend of the suspect being sought in the shooting in the back of a taxi, where he could be seen peering through the open slider in the partition between the seats.
Another photo appeared to show the man walking by the window of a cab.
Photos taken in the lobby of a hostel on Manhattan's Upper West Side showed the suspect grinning after removing his mask, police said.
Backpack contained Monopoly money
Police found a backpack believed to belong to the suspected shooter in Central Park on Friday evening, police sources told ABC News. The backpack contained fake money from the game Monopoly and a Tommy Hilfiger jacket, sources said.
The backpack was found after NYPD deployed an army of officers and drones to conduct a grid search, police sources said earlier.
As of Saturday, three days after the shooting, sources close to the investigation told ABC News the New York Police Department is making progress toward identifying the gunman but, as of now, still has not done so.
On Friday, police said they believed the gunman left New York City following the shooting -- ditching his bike on the Upper West Side and taking a taxi to a Port Authority bus facility at 178th Street. Police said they believe he boarded a bus there because they did not see him on video leaving the facility.
Suspect stayed at hostel
The NYPD released on Thursday new photos of the suspect, seen without a mask, while asking for the public's help in identifying him. The images were taken from a surveillance camera at the HI New York City Hostel on Manhattan's Upper West Side. Police had obtained a warrant to search after coming to believe the suspect stayed there, sources told ABC News.
Police were able to find an image of the suspect without his face mask because he was flirting with the woman who checked him into the hostel, police sources told ABC News.
As he stood at the check-in desk, the sources said the woman asked to see his smile. The suspected shooter obliged, pulling down his mask long enough for the surveillance camera to capture his face.
It appears the suspect shared a room with two other men, according to police sources.
The suspect likely checked into the hostel on Nov. 24, checked out and then checked back in again on Nov. 30, according to sources. It's not clear when the surveillance image was captured.
The suspected shooter checked into the hostel using a New Jersey license that wasn't his own, according to police sources. Detectives ran the name and found it did not resemble any known photos of the suspect or other evidence amassed so far, the sources said.
Suspect arrived in NYC 10 days before shooting: Sources
The suspect came to New York City on Nov. 24 on a Greyhound bus, when a surveillance camera at Port Authority Bus Terminal caught his arrival at 9 p.m., law enforcement sources told ABC News.
The inbound bus originated in Atlanta but it was not immediately clear where the suspect boarded. The sources said he was spotted on board in Washington, D.C., so he boarded there or somewhere between D.C. and Atlanta.
Both Greyhound and the parent company of the hostel, Hostelling International USA, said in a statement that they are "fully cooperating with the NYPD" but cannot comment further due to the active investigation.
The 10-day period had been the focus of investigative efforts. Police collected a lot of video of the suspect all over the city -- in the subway, in cabs, in a McDonald's, according to sources. Each place he paid with cash and he made sure to keep his mask on, according to sources.
Tracing how the suspect left the city after the murder
Retracing the gunman's steps using surveillance video, investigators say the shooter fled into Central Park on a bicycle, emerged from park without his backpack and then ditched the bicycle.
He then walked a couple blocks and got into a taxi, arriving at at the George Washington Bridge Bus Station, which is near the northern tip of Manhattan and offers commuter service to New Jersey and Greyhound routes to Philadelphia, Boston and Washington, NYPD Chief of Detectives Joseph Kenny said.
The FBI announced late Friday that it was offering a $50,000 reward for information leading to an arrest and conviction, adding to a reward of up to $10,000 that the NYPD has offered. Police say they believe the suspect acted alone.
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Some information from ABC News and the Associated Press
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