The gun found on Mangione when he was arrested in Pennsylvania matched shell casings found at the shooting scene in midtown Manhattan, New York City Police Commissioner Jessica Tisch said Wednesday, adding that his fingerprints also matched prints on a water bottle and protein bar wrapper found near the crime scene. Police have said they believed the gunman bought them at a nearby coffee shop while awaiting his target.

Writings found in Mangione’s possession hinted at a hatred of corporate greed, authorities have said. Among the items investigators have recovered was a spiral notebook, along with a three-page handwritten letter found when he was arrested, a law enforcement official said Wednesday. The official wasn’t authorized to disclose information about the investigation and spoke to The Associated Press on the condition of anonymity.

Police have not disclosed what was in the notebook, but Mangione said in his letter that it would contain clues about the attack, according to the official.

In addition to the letter, arresting officers also found Mangione to be carrying a ghost gun, which is a type of firearm that can be assembled at home and is difficult to trace. NYPD Chief of Detectives Joseph Kenny said Monday.

Officers also found a sound suppressor, or silencer, “consistent with the weapon used in the murder,” New York Police Commissioner Jessica Tisch said. He had clothing and a mask similar to those worn by the shooter and a fraudulent New Jersey ID matching one the suspect used to check into a New York City hostel before the shooting, the commissioner said.

Kenny told CBS New York on Tuesday that no prints were found on the bullets that killed Thompson, but there was one fingerprint on a cellphone that was recovered. He said the evidence was being processed.

Kenny also suggested that the motive might have been related to an accident that sent Mangione to an emergency room on July 4, 2023.

Mangione, who comes from a prominent Maryland family, was valedictorian of his elite Baltimore prep school and had degrees from one of the nation’s top private universities. He earned undergraduate and graduate degrees in computer science in 2020 from the University of Pennsylvania.

From January to June 2022, Mangione lived at Surfbreak, a “co-living” space at the edge of touristy Waikiki in Honolulu. Josiah Ryan, a spokesperson for owner and founder R.J. Martin, said that Martin had learned that Mangione had severe back pain from childhood that interfered with many aspects of his life.

A law enforcement bulletin obtained by the AP earlier this week said Mangione likely was motivated by his anger at what he called “parasitic” health insurance companies and a disdain for corporate greed. He wrote that the U.S. has the most expensive health care system in the world and that the profits of major corporations continue to rise while “our life expectancy” does not, according to the bulletin, which law enforcement said was based on a review of Mangione's handwritten notes and social media posts.

Investigators are also looking at Mangione’s Facebook page, where he posted X-rays of numerous screws that were inserted into his spine, as well as writings in which he discussed the difficulty of sustaining that injury.

In his first public words since his arrest, Mangione shouted about an “insult to the intelligence of the American people” as he was escorted into the courthouse Tuesday.

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Associated Press reporters Michael R. Sisak, Jamie Stengle and Lea Skene contributed to this report.

12/11/2024 17:34 -0500

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