The man charged with killing UnitedHealthcare CEO Brian Thompson was never a client of the medical insurer and may have targeted it because of its size and influence, a senior police official said.

NYPD Chief of Detectives Joseph Kenny told NBC New York in an interview that investigators have uncovered evidence that Luigi Mangione had prior knowledge UnitedHealthcare was holding its annual investor conference in New York City.

Mangione also mentioned the company in a note found in his possession when he was detained by police in Pennsylvania.

"We have no indication that he was ever a client of United Healthcare, but he does make mention that it is the fifth largest corporation in America, which would make it the largest healthcare organisation in America. So that's possibly why he targeted that company," said Kenny.

This booking photo provided by Pennsylvania Department of Corrections shows Luigi Mangione, a suspect in the fatal shooting of UnitedHealthcare CEO Brian Thompson. (Source: Associated Press)

ADVERTISEMENT

Mangione remained jailed without bail in Pennsylvania, where he was arrested after being spotted at a McDonald's in the city of Altoona, about 370km west of New York City.

His lawyer there said he hadn't seen any evidence yet linking him to the crime.

Mangione's arrest came five days after the caught-on-camera killing of Thompson outside a Manhattan hotel.

Police said the shooter waited outside the hotel, where the health insurer was holding its investor conference, early on the morning of December 4. He approached Thompson from behind and shot him before fleeing on a bicycle through Central Park, then heading to a bus depot.

UnitedHealthcare chief executive officer Brian Thompson. (Source: Associated Press)

Mangione was fighting attempts to extradite him back to New York to face a murder charge in Thompson's killing. A hearing has been scheduled for December 30.

The 26-year-old, who police say was found with a "ghost gun" matching shell casings found at the site of the shooting, is charged in Pennsylvania with possession of an unlicensed firearm, forgery and providing false identification to police. His lawyer, Thomas Dickey, said his client was not guilty.

ADVERTISEMENT

Mangione was an Ivy League graduate from a prominent Maryland real estate family.

Police said investigators were looking into an accident that injured Mangione's back and sent him to an emergency room in July 2023.

More on this topic

US CEO killing: Suspect struggles, shouts while entering courthouse

Luigi Nicholas Mangione, a 26-year-old Ivy League graduate, was arrested in the shooting of health insurance boss Brian Thompson.

Crime and Justice

Wed, Dec 11

2:24

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

The motive might be related to an accident that sent Luigi Mangione to an emergency room in 2023, police said.

Crime and Justice

Thursday 8:25am

They were also looking at his writings about the injury and his criticism of corporate America and the US health care system.

Kenny said in the NBC interview that Mangione's family reported him missing to San Francisco authorities in November.