UnitedHealthcare CEO killing: Gun found on suspect matches shell casings at scene

The gun found on the suspect in the killing of UnitedHealthcare CEO Brian Thompson matches shell casings found at the crime scene in New York City, police said. 

New York Police Commissioner Jessica Tisch said lab results matched Luigi Mangione's prints to a water bottle and protein bar wrapper found near the scene of Thompson's killing outside a Hilton Hotel on Dec. 4, the Associated Press reports. 

Luigi Mangione charged in Thompson's killing

What we know: Mangione, 26, is charged in New York with the fatal shooting of Thompson. He also faces weapons and fake ID charges out of Pennsylvania, where he was arrested on Monday. 

Thompson was shot and killed near West 54th Street and 6th Avenue outside the Hilton Hotel in Manhattan around 6:45 a.m. ET on Dec. 4, 2024. Thompson was set to take part in the company's investor conference at the hotel.

Video shows the gunman firing shots from behind Thompson, striking him several times.

Authorities say the words "deny," "defend," and "depose" – a phrase critics use to describe insurance company tactics – were written on the ammo casings left behind at the scene. New York City police believe the shooting was premeditated and targeted.

Despite an extensive search and heavy media coverage, police had not been able to make an arrest in the shooting.Over the weekend, police released a new batch of photos showing the masked gunman riding in a cab and increased the reward for information leading to an arrest to $50,000, up from $10,000. On Friday, police reportedly found a distinctive backpack that the gunman was wearing. Inside, they found a jacket and Monopoly money. According to reports, investigators were also testing a discarded water bottle and protein bar wrapper for DNA.

What's next: Mangione remains jailed without bail in Pennsylvania. During a court hearing Tuesday, he did not agree to extradition to New York to face charges there and wants a hearing on the matter. 

Search for Mangione

Timeline: Here's a timeline of events leading up to the shooting and the manhunt for the suspect.  

Nov. 24:

  • 10:11 p.m. ET on Sunday, Nov. 24: The suspected shooter arrives in New York City on a Greyhound bus at the Port Authority terminal on a bus that originated in Atlanta, Georgia. The bus made six or seven stops on the way to New York. Police could not immediately determine where he got on the bus. The man then took a taxi to the area of New York Hilton Midtown and is there for about a half-hour.
  • About 11 p.m. ET on Sunday, Nov. 24: The man takes a taxi to the HI New York City Hostel at 891 Amsterdam Ave., where he stays until the morning of the shooting. He presents an ID that police believe to be fake. Two roommates in a shared room that had bunkbeds never saw his face, police said, because he kept his mask on. When speaking with an employee in the hostel lobby, he briefly pulled down his facemask and smiled — a moment captured on surveillance images that have been widely circulated by police.

Nov. 29:

  • Friday, Nov. 29: The man was checked out of the hostel, where guests are automatically checked out if they don’t show at the desk by a certain time. Police don’t believe he stayed someplace else and checked back into the same hostel the next day.

Dec. 4:

  • About 5:30 a.m. ET on Dec. 4: The suspected shooter leaves the hostel well before dawn.
  • 5:41 a.m. ET on Dec. 4: He appears on video at 54th Street and Sixth Avenue walking back and forth in the area of the Hilton hotel where United Healthcare’s parent company, UnitedHealth Group, is holding its annual investor conference.

Police deduce that he rode a bicycle to the Hilton because it took him such a short time to get there. "Could he have stolen the bike? These are things we’re still looking into," NYPD Chief of Detectives Joseph Kenny said.

At some point, he went to a nearby Starbucks and purchased a bottle of water and at least one energy bar before returning to the hotel.

  • 6:44 a.m. ET on Dec. 4: He shoots Thompson as the executive arrives alone, on foot, having walked from a hotel across the street. The man flees.
  • 6:48 a.m. ET on Dec. 4: The man enters Central Park by bicycle at the 60th Street and Center Drive entrance. It's in the park and away from security cameras that police believe he discarded a gray backpack.
  • 6:56 a.m. ET on Dec. 4: He leaves the park at West 77th Street and Central Park West, still on the bicycle.
  • 6:58 a.m. ET on Dec. 4: He passes another camera on 85th Street and Columbus Avenue, still on the bicycle.
  • 7 a.m. ET on Dec. 4: He's at 86th Street, no longer with the bicycle.
  • 7:04 a.m. ET on Dec. 4: He enters a taxi northbound at 86th Street and Amsterdam Avenue.
  • 7:30 a.m. ET on Dec. 4: He's near the George Washington Bridge and the bus terminal there. It offers commuter service to New Jersey and Greyhound routes to Philadelphia, Boston and Washington.

After the attack, investigators find the words "deny," "defend" and "depose," written in permanent marker on ammunition at the scene. The words mimic a phrase used by insurance industry critics.

Dec. 6:

Kenny and Police Commissioner Jessica Tisch reveal that investigators believe the gunman left New York City on a bus. Investigators say he entered the George Washington Bridge Bus Station but have not found video of him leaving or getting on a bus.

"It could possibly be a disgruntled employee, or a disgruntled client," Kenny says of a possible motive in a briefing.

Police found what they said was the man's backpack. Its contents are not disclosed.

Dec. 7:

Police continue to search Central Park; scuba divers are seen scouring a pond. The NYPD releases additional photos showing the suspected shooter next to and in the back seat of a taxi. In both images, he is seen wearing a blue, medical-style face mask.

Despite recovering a fingerprint from the Starbucks purchase and sending items for DNA testing, police have yet to publicly identify the suspect.

Dec. 8:

Scuba divers are again seen at a Central Park pond. Police declined to comment on the investigation.

Dec. 9:

  • 9:15 a.m. ET on Dec. 9: Police take Luigi Mangione into custody for questioning at a McDonald's in Altoona, Pennsylvania, after an employee noticed similarities between him and the alleged gunman. On Monday afternoon, NYPD authorities announced Mangione was a "strong person of interest" in the case, and he was charged later that day in Pennsylvania with weapons and fake ID charges and then with a murder charge in New York.

Ongoing impact of the CEO's killing

Dig deeper: The shooting has also increased concerns for other healthcare companies.

Last week, Medica announced it was closing its Minnesota headquarters out of an abundance of caution in the wake of the shooting. 

UnitedHealthcare has also put up a fence around its building. 

In a statement to FOX 9 on Monday, UCare, a Minneapolis-based nonprofit health plan, also confirmed it was closing its offices for the week following a "concerning comment" in a phone call.

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