(CNN) — New York prosecutors have charged Luigi Mangione with murder in the assassination of UnitedHealthcare CEO Brian Thompson, hours after he was apprehended at a McDonald’s in Altoona, Pennsylvania, on Monday.

The 26-year-old Ivy League graduate from Maryland was also charged with 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 criminal possession of a firearm, online court documents show.

The fatal shooting of Thompson outside an investors’ conference in Midtown Manhattan sparked an exhaustive search, with New York police combing the city for evidence and poring through thousands of hours of video footage.

The breakthrough came after five days, on Monday morning, when an employee at a McDonald’s in Altoona, about 230 miles from the hotel where the shooting happened, called police saying that they had identified the suspect.

Luigi Mangione is seen in an image released by the Pennsylvania Deptartment of Corrections.

When two police officers arrived, they found a man “wearing a medical mask and a beanie” sitting “in the rear of the building at a table,” looking at a laptop, according to a criminal complaint released Monday.

Officers asked him to pull down the mask to see his face and “immediately recognized him as the suspect,” according to the criminal complaint.

The officers asked the man for identification and he gave them a New Jersey ID with the name Mark Rosario. When they asked whether he had been to New York City recently, he “became quiet and started to shake,” the criminal complaint says.

Police were unable to find any records that matched the ID given and told the man he was under an official police investigation. He then told officers his real name: Luigi Mangione.

When an officer asked why he had used a false name, he replied, “I clearly shouldn’t have,” according to the complaint.

After arresting Mangione, police found “a black 3D-printed pistol” with a loaded Glock magazine and a “black silencer” that was also 3D-printed in his backpack, says the criminal complaint. New York Police Commissioner Jessica Tisch said earlier in the day Mangione was found with a gun and a suppressor “both consistent with the weapon used in the murder,” referring to a device that muffles the sound of a firearm.

The NYPD chief of detectives, Joseph Kenny, previously described the weapon found with Mangione as a “ghost gun,” an untraceable weapon, and capable of firing a 9 mm round.

Authorities also recovered a “fraudulent New Jersey ID matching the ID our suspect used to check into his New York City hostel before the shooting,” Tisch said, and “a handwritten document that speaks to both his motivation and mindset.” Kenny said the document, which has also been described as the suspect’s “manifesto,” did not include specific threats but indicated “ill will towards corporate America.”

“These parasites had it coming,” one line from the document reads, according to a police official who has seen it. Another reads, “I do apologize for any strife and trauma, but it had to be done.” The document indicates the suspect acted alone and that he was self-funded, according to Kenny.

The suspect also appeared to make a reference to UnitedHealthcare describing “United” as one of the largest companies by market capitalization in the United States, according to a law enforcement source who has read the document. There is no mention of Thompson specifically.

In addition to the weapon and fake ID found on the suspect, Tisch said, police recovered “clothing, including a mask, consistent with those worn by our wanted individual.”

The NYPD and FBI arrived in Altoona on Monday afternoon, according to Republican Rep. John Joyce of Pennsylvania.

Mangione was interviewed by police at the Altoona Police Department, an officer told CNN, before he was taken to the Blair County courthouse.

He was temporarily assigned a public defender at his first court appearance. CNN has not yet identified his attorney.

Altoona Police arrested 26-year-old Luigi Mangione, the suspect in the fatal shooting of UnitedHealthcare CEO Brian Thompson, New York City Police Commissioner Jessica Tisch said in a news conference Monday. This photo was posted in 2019.

Pennsylvania State Police said they believe Mangione had been in the state for “several days.” Lt. Col. George Bivens said at a Monday news conference that as the investigation progresses he is “confident we’ll have a much better idea of his activities over the past, you know, number of days in New York and in Pennsylvania.”

“We’ve already identified businesses, for example, that he frequented in this area and activities that he engaged in — that led us to more evidence, and so all of that is becoming kind of a mountain of evidence that has to be analyzed and looked at.”

Pennsylvania Gov. Josh Shapiro said the suspect had traveled between Pittsburgh and Philadelphia, making stops in between.

The head of the private school from which Mangione graduated from sent an email to parents and members of the school community, calling the news “deeply distressing.”

“This is deeply distressing news on top of an already awful situation. Our hearts go out to everyone affected,” Gilman School Headmaster Henry P.A. Smyth said in the email.

UnitedHealth Group hopes “today’s apprehension brings some relief to Brian’s family, friends, colleagues, and the many others affected by this unspeakable tragedy,” a spokesperson said in a statement.

“We thank law enforcement and will continue to work with them on this investigation. We ask that everyone respect the family’s privacy as they mourn,” the spokesperson said.

In a statement released through Mangione’s cousin, Nino Mangione, who is a Maryland state delegate, the suspect’s family said that they are “shocked and devastated by Luigi’s arrest.”

“We offer prayers to the family of Brian Thompson and we ask people to pray for all involved,” the statement said, signed with “The Mangione Family.”

The note said that the family only knows the facts of the case that have been released in the news and they are “devastated by the news.”

Here’s more of what we know about the suspect:

  • Mangione was born and raised in Maryland and his last known address was in Honolulu, according to Kenny. He had no history of arrests in New York, said the chief of detectives.
  • Mangione graduated from Gilman School – a prestigious all-boys school in Baltimore, where he served as valedictorian – and the University of Pennsylvania, an Ivy League university in Philadelphia, with a master’s and bachelor’s degree in computer science and a minor in mathematics.
  • One former classmate who said they studied alongside Mangione at the University of Pennsylvania described him as a “totally normal guy.”
  • A Goodreads profile that appears to belong the suspect shows that earlier this year, he reported having read the 1995 antitechnology manifesto written by the Unabomber Ted Kaczynski, the infamous domestic terrorist and mathematician known for sending deadly bombs through the mail between 1978 and 1995.

How the investigation unfolded

Catching the suspect came down to “good old-fashioned police work,” New York Mayor Eric Adams said Monday, citing the McDonald’s employee who called in a tip.

“For just over five days, our NYPD investigators combed through thousands of hours of video, followed up on hundreds of tips, and processed every bit of forensic evidence: DNA, fingerprints, IP addresses, and so much more, to tighten the net,” said police commissioner Tisch.

Authorities knew what the suspect looked like but not who or where he was. Over the weekend, they released new photos of him: in the backseat of a taxi and wearing a jacket while walking on the street. In both, he wears a hood and a face mask.

The public, too, had seen the suspect in surveillance photos and videos, including one with him pointing the weapon at Thompson’s back.

This image shows a firearm found while searching the suspect.

Some of the suspect’s actions – such as pulling his mask down on camera, and leaving behind inscribed shell casings that may point to a motive, a burner phone and a partial fingerprint on a water bottle – only added to the clues authorities could use.

Police continue to look into whether words found on the casings – “Deny,” “Defend,” and “Depose” – may point to a motive. A 2010 book critiquing the insurance industry is titled, “Delay Deny Defend,” a common description of the industry’s tactics.

Here are other key developments:

  • Still missing is an electric bike the suspect rode toward Central Park after the shooting, according to surveillance images released by authorities. Divers previously searched a lake in Central Park for the weapon used in the shooting, a law enforcement official told CNN.
  • A partial fingerprint and DNA recovered early in the search for the suspect have so far not yielded matches when compared against law enforcement databases, according to a law enforcement official. The fingerprint was recovered from a purported “burner phone” thought to belong to the suspect, and the DNA from a water bottle and energy bar wrapper the suspect is said to have bought.
  • A backpack believed to be the suspect’s was recovered Friday in Central Park, a law enforcement source said. It contained money from the Monopoly board game, a law enforcement source told CNN, and a Tommy Hilfiger jacket, law enforcement officials briefed on the matter said.

This story has been updated with additional information.

CNN’s Danny Freeman, Elise Hammond, Melanie Hicken, Blake Ellis, and Brian Todd contributed to this report.