UnitedHealthcare CEO killing possible motive: Luigi Mangione yells to press outside courthouse

NEW YORK — Luigi Mangione, a 26-year-old accused of gunning down UnitedHealthcare CEO Brian Thompson outside a Midtown Manhattan hotel last week, considered the slaying to be a “symbolic takedown” of UnitedHealthcare over perceived corruption, according to a confidential assessment of the crime by the NYPD intelligence bureau described to ABC News.

Mangione “appeared to view the targeted killing … as a symbolic takedown and a direct challenge to its alleged corruption and ‘power games,'” the assessment said, according to a source. Mangione allegedly described himself as the “first to face” United Healthcare “with such brutal honesty.”

The assessment is based in part on the suspect’s writings.

When Mangione was arrested on Monday he had “written admissions about the crime” with him, according to the New York arrest warrant.

Mangione had several handwritten pages on him that expressed a “disdain for corporate America” and indicated “he’s frustrated with the health care system in the United States,” NYPD Chief of Detective Joe Kenny told ABC News’ “Good Morning America” on Tuesday.

“Specifically, he states how we are the No. 1 most expensive health care system in the world, yet the life expectancy of an American is ranked 42 in the world,” Kenny said.

Whether Mangione has a personal connection to UnitedHealthcare is unknown, NYPD Commissioner Jessica Tisch said, but the writings mention UnitedHealthcare by name, law enforcement sources told ABC News.

The sources described the handwriting as sloppy and included these quotes: “These parasites had it coming” and “I do apologize for any strife and trauma, but it had to be done.”

Mangione — who was arrested in Altoona, Pennsylvania, on Monday in connection with Thompson’s Dec. 4 slaying — is in custody in Pennsylvania and is set to appear at an extradition hearing at 1:30 p.m. Tuesday.

The NYPD was “thrilled” to get the call from Altoona police that they had a person of interest in custody, Tisch told “GMA.”

Kenny said “the key to this case” was releasing photos of the suspect’s face to the media and the public.

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“That picture reached Pennsylvania,” where Mangione was recognized at a McDonald’s on Monday morning, Kenny said.

“We are grateful as a city to that person,” Tisch said.

“We had collected early in the investigation some forensic evidence, some DNA evidence, some fingerprints, so we were very confident that we were ultimately going to get to the right person,” Tisch added.

“We do have a lot of evidence in this case,” Tisch told “GMA.”

Mangione was apprehended “in possession of the same New Jersey fake identification that was used” to check into a hostel on New York’s Upper West Side before Thompson was gunned down, she said.

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The gun Mangione was allegedly found with on Monday “looks very similar” to the gun used in the murder, “with a similar suppressor,” Tisch said. “So there’s a lot of reasons that we feel very strongly that he is the person of interest.”

Officers allegedly found a 3D printed pistol and a 3D printed silencer, according to the criminal complaint filed in Pennsylvania.

“The pistol had one loaded Glock magazine with six nine-millimeter full metal jack rounds. There was also one loose nine-millimeter hollow point round,” the complaint said.

Kenny described the weapon as a “ghost gun,” meaning it had no serial number and was untraceable.

Mangione, a Maryland native and Ivy League graduate, has been charged in New York with second-degree murder, possession of a loaded firearm, possession of a forged instrument and criminal possession of a weapon.

He was charged with five crimes in Pennsylvania, including carrying a gun without a license, forgery, falsely identifying himself to authorities and possessing “instruments of crime,” according to the criminal complaint.

Mangione’s family said in a statement that they’re “shocked and devastated by Luigi’s arrest. We offer our prayers to the family of Brian Thompson and we ask people to pray for all involved.”

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The Pennsylvania State Police is asking for the public’s help piecing together Mangione’s travel in Pennsylvania. Anyone with information is asked to call 1-800-4PA-TIPS.

Police are also looking at Mangione’s travel at various points across the United States and out of the county within the past year, sources said.

This is a developing story. Please check back for updates.