Police have arrested a “person of interest” in connection with the brazen murder of the chief executive of UnitedHealthcare, Brian Thompson, according to the New York City police commissioner, Jessica Tisch. 

During a press conference on Monday, Ms. Tisch said a 26-year-old man, identified as Luigi Mangione, was found with multiple fake IDs, including a fake New Jersey driver’s license and a gun believed to be similar to the one used by the gunman behind Thompson’s murder at Manhattan.

He was first apprehended and questioned at a McDonald’s at Altoona, Pennsylvania.

Ms. Tisch said Mr. Mangione was arrested on firearms charges. The chief of detectives, Joseph Kenny, told reporters that officials had not learned the suspect’s name until Monday.

Police also reportedly discovered some kind of documents in Mr. Mangione’s possession critical of the healthcare industry that they believe are related to the shooting and could point to a motive. The New York Police Department sent detectives to question him.

Mr. Mangione was spotted by a McDonald’s employee who reportedly recognized the man from pictures of the suspect circulating online. Police at Altoona also reportedly recovered a computer and clothing, including a mask.

A cryptic unverified YouTube account bearing the suspect’s name has a video that was timed to post hours after his arrest titled “The Truth.” The video is roughly one and a half minutes long and features a black-and-white clock with a countdown ticking down. On the screen is text that reads, “The Truth…If you see this, I’m already under arrest.” At the end of the video, the word “Soon” appears on the screen. 

“All is scheduled, be patient. Bye for now,” text on the screen tells viewers. A second video is scheduled to publish Monday evening at 6:45 pm eastern time.

Mr. Mangione, from Towson, Maryland, graduated valedictorian from a prep school, the Gilman School at Baltimore. He also studied artificial intelligence at the University of Pennsylvania and has a bachelor’s and a master’s degree in computer science. 

His parents are the owners of a country club in Maryland, and one of his cousins, Nino Mangione, is a Baltimore County delegate.  The delegate’s office confirmed to NBC News that he is related to the suspect in the murder of Thompson. 

Law enforcement officials told the New York Post he supported “anti-capitalist and climate change” causes and also shared his hatred of the healthcare industry. His Goodreads profile shows that he liked quotes from a variety of individuals, from Socrates to the “Unabomber,” Ted Kaczynski.

Mr. Mangione left a four-star comment on Kaczynski’s manifesto on Goodreads and called the Unabomber an “extreme political revolutionary,” not a “crazy luddite.” He also wrote, “When all other forms of communication fail, violence is necessary to survive.”

Screenshots from Mr. Mangione’s Goodreads and social media feeds showed he had read material about chronic back pain, which has led to speculation that he or someone he knew was in physical pain for which he may have held health insurers responsible. 

Thompson’s murder resulted in a wave of vitriol directed at health insurance companies over the way they sometimes deny claims. 

After officials disclosed Mr. Mangione’s identity, the hashtag “FREE HIM” started to trend on X. One user on the social media platform wrote, “Luigi mangione basically killing the ceo of the insurance that f***ed over his grandparents. that man is a hero and avenged their deaths. FREE HIM.”

“Um… most people feel the same way. That’s why we’re rooting for this guy. FREE HIM,” one user wrote after sharing a post stating the suspect had “ill-will toward corporate America.”

Another user shared a shirtless picture of Mr. Mangione, in which he appeared to be in good shape, and wrote, “Waaait FREE HIM.”

Thompson’s murder at midtown Manhattan on Wednesday set off a six-day manhunt as law enforcement searched for the elusive gunman. Officials maintain that the shooting appeared to be “targeted,” noting that the masked gunman appeared to have had an extensive plan and had been laying in wait for the chief executive.

The gunman shot Thompson multiple times from behind, surveillance video shows. Police say the shooter then fled down an alleyway and used an electric bike to escape to Central Park.

Officials said the suspect arrived in New York City on November 24, more than a week before the shooting, and that he checked into a hostel on the Upper West Side using a fake driver’s license from New Jersey. 

A law enforcement analyst for CNN, John Miller, reported that the name on the New Jersey license found on the man at Altoona may match the one used by the gunman to check into the hostel.

Police have not identified a motive in the shooting. However, sources told multiple news outlets that investigators recovered bullet cases with the words “delay” and “depose” written on them at the crime scene. The disclosure of the words sparked speculation that they referred to a popular phrase in the healthcare insurance industry, “delay, deny, defend,” when companies deny claims, which some commentators and analysts suggested could point to a motive.