New York Police Commissioner Jessica Tisch says crime lab analysis shows matches to gun, snack wrapper and water bottle.

Fingerprints and shell casings connect murder suspect Luigi Mangione to the scene of the killing of UnitedHealthcare chief executive Brian Thompson, the police commissioner of New York City has said.

Police Commissioner Jessica Tisch told reporters on Wednesday that a home-assembled gun allegedly found in Mangione’s possession matched three shell casings found at the scene.

Mangione’s fingerprints were also found on a water bottle and the wrapper of a Kind bar recovered nearby, Tisch said.

Mangione, 26, was arrested on Monday at a McDonald’s outlet in Altoona, Pennsylvania, after an employee contacted police.

Police say that Mangione, who comes from a prominent family in Maryland, was found with a so-called ghost gun, fake IDs and a handwritten note discussing possible motives.

The University of Pennsylvania graduate is currently being held without bail in western Pennsylvania as he fights efforts to extradite him to New York to face murder, firearms and forgery charges.

Mangione’s lawyer, Thomas Dickey, told US media he has not “seen any evidence yet” implicating his client in the murder.

“I don’t want people to jump to these prejudgement things because nobody would ever want that if they were accused, or one of their loved ones were accused,” Dickey told Chris Cuomo on his NewsNation show on Tuesday.

Thompson, 50, was shot dead outside the New York Hilton Midtown hotel on December 4 while on his way to his company’s annual investor conference.

Thompson’s killing sent shockwaves throughout corporate America, prompting discussion about whether executives need greater security protection.

The father of two’s death has also unleashed a flood of morbid glee amid widespread public frustration over the quality and cost of US healthcare.