A 26-year-old man has been arrested in connection with last week's fatal shooting in New York City of UnitedHealthcare CEO Brian Thompson.
Luigi Mangione, 26, was taken into custody at a McDonald's in the town of Altoona, Pennsylvania, about 280 miles (450km) west of New York City on Monday after a customer at the fast-food outlet recognised the suspect.
He was found in possession of a handwritten document that indicated "motivation and mindset", according to police.
Mr Mangione later appeared in a Pennsylvania court to be arraigned on five initial counts and was denied bail. A prosecutor said he expected a homicide charge to be filed soon.
Mr Mangione was formally charged on Monday evening with forgery, carrying firearms without a licence, tampering with records or identification, possessing instruments of crime and providing a false identification to police.
Pete Weeks, a district attorney in Pennsylvania's Blair County, said that homicide charges from New York would be filed "tonight or tomorrow" or in the "near future".
Mr Mangione stopped co-operating after he was detained, officials said.
A handcuffed Mr Mangione appeared in court on Monday, wearing jeans and a dark blue jersey. He appeared calm in court, occasionally looking around at those present, including the media.
New York City investigators used one of the world's largest digital surveillance systems, police dogs, drones and divers in a Central Park lake in the search for clues before the manhunt spread to neighbouring states.
But it appears a McDonald's customer recognised the suspect from media coverage and alerted an employee, who tipped off the authorities.
According to authorities in Pennsylvania, officers were called to a report of a "suspicious male" who resembled the suspect in Thompson's murder.
When officers arrived at the fast-food restaurant, Mr Mangione showed them a fake New Jersey driver's licence with the name Mark Rosario, said court papers.
He "became quiet and started to shake" when an officer asked if he had been to New York recently, the criminal complaint adds.
When he was told he would be arrested if he lied about his name, he admitted he was Luigi Mangione, according to the court papers.
When asked why he lied, he told officers that "I clearly shouldn't have", said the court papers.
A search of his backpack uncovered a 3D-printed black printer, a 3D-printed silencer and a loaded magazine with six rounds of 9mm ammunition.
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Earlier in the day, New York Police Commissioner Jessica Tisch said the weapon and suppressor seized by investigators from the suspect were "both consistent with the weapon used in the murder".
Once any charges in New York are filed, Mr Mangione will be presented with the option of waiving his extradition or contesting it.
If he waives it, he will immediately be made available to New York authorities. If he contests it, the process could take between 30 and 45 days.
A three-page handwritten document found on Mr Mangione's possession suggested he harboured "ill will towards corporate America", said New York Chief of Detectives Joseph Kenny.
Mr Kenny said that Mr Mangione was born and raised in Maryland and has ties to San Francisco, California.
Authorities believe he may have attended university in Pennsylvania, but his last known address was in Honolulu, Hawaii.
TrueCar, a website for car buyers, confirmed that he had been employed there but left in 2023.
As a teenager, Mr Mangione attended a private all-boys school in Maryland, where he was class valedictorian.
A LinkedIn account that appears to belong to him says he worked as a data engineer in California, and graduated from the University of Pennsylvania, where he was a teaching assistant and founded a video game development club.
Several posts to an account on X, formerly Twitter, that appeared to belong to him suggested that friends had been trying to reach him, with one person posting in October that "nobody has heard from you in months".
Thompson, 50, was fatally shot in the back last Wednesday morning outside the Hilton hotel in Midtown Manhattan where UnitedHealthcare, the medical insurance giant he led, was holding an investors' meeting.
Police say he was targeted in a pre-planned killing.
The words "deny", "defend" and "depose" were written on shell casings found at the scene.
Investigators believe they could be a reference to what critics call the "three Ds of insurance" - tactics used by insurance companies to reject payment claims by patients in America's complicated and mostly privately run healthcare system.
(Additional reporting by Cai Pigliucci and Mike Wendling)