Authorities on Wednesday confirmed that the gun recovered in the arrest of Luigi Mangione earlier this week is linked to shell casings found at the scene of the killing of UnitedHealthcare CEO Brian Thompson.
The development comes after investigators said they were also analyzing a fingerprint left on a cellphone that was found at the scene of the slaying that could potentially be that of Mangione, who was taken into custody this week in connection to the assassination. CNN reports that the fingerprint is Mangione's, according to two law enforcement officials briefed on the matter.
Mangione, 26, was arrested Monday at a McDonald's in Altoona, Pennsylvania, after police received a tip about a man matching the description of the individual wanted in connection to the New York City killing.
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A police report says Mangione initially presented officers with a fake ID. It had the same name police said Mangione used at a hostel in New York prior to allegedly killing Thompson, police said.
When confronted about the fake ID, police said Mangione told them his real name. He was then placed under arrest.
Police said they found a pistol in Mangione's backpack that had a metal slide and barrel and a plastic handle. They also found a plastic suppressor, six 9mm bullets in a Glock magazine and one loose round.
Authorities believe the firearm was a "ghost gun" that was likely made with a 3D printer.
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While police haven't revealed a definitive motive, writings recovered during Mangione's arrest could shed light on his mindset. NYPD Chief of Detectives Joseph Kenny said the materials suggested Mangione harbored "ill will toward corporate America."
Mangione has been charged with murder, along with firearms and forgery offenses. He is currently being held in a state prison in Huntingdon County, Pennsylvania. A judge on Tuesday ordered Mangione to remain behind bars, not allowing him to post bail.