Note by UnitedHealthcare murder suspect

Luigi Mangione had a handwritten note that said, “These parasites had it coming,” when he was nabbed in Pennsylvania by police who recognized him as the suspect wanted for killing UnitedHealthcare‘s CEO, NBC News reported Tuesday.

Mangione, 26, also wrote that he was not “working with anyone” when he allegedly fatally shot CEO Brian Thompson last Wednesday outside the Hilton Hotel in midtown Manhattan.

“I do apologize for any strife or traumas but it had to be done,” Mangione wrote in the note, according to three law enforcement sources who spoke to NBC News.

“Frankly, these parasites simply had it coming.”

The three-page note criticized UnitedHealthcare, the broader U.S. health-care industry and corporations.

An arrest warrant for Mangione in New York state court refers to the note as “written admissions about the crime” of killing Thompson.

Mangione on Monday night was charged by the Manhattan District Attorney’s Office with murder and gun crimes in connection, hours after Pennsylvania authorities charged him with firearms crimes and forgery.

Mangione is due in court at 1:30 p.m. ET Tuesday in Hollidaysburg, Pennsylvania, for a hearing on his likely extradition to New York to face the murder case.

UnitedHealthcare, a division of UnitedHealth Group, is the largest private payer of health insurance benefits in the U.S., with more than $280 billion in annual revenue.

Police believe Mangione intentionally targeted Thompson in the killing, which occurred as the 50-year-old father of two was headed into a UHG investor day meeting in the Hilton.

“To the Feds, I’ll keep this short, because I do respect what you do for our country,” Mangione wrote in his note.

“To save you a lengthy investigation, I state plainly that I wasn’t working with anyone.”

Mangione, who is part of a wealthy Baltimore-area family, and who reportedly suffers from chronic back pain, was charged by the Manhattan District Attorney’s Office with murder and gun crimes hours after his apprehension in Pennsylvania.

He is being held in a state prison in Pennsylvania after being denied bail Monday night following his arrest earlier in the day in a McDonald’s in Altoona.

Altoona Police went to the restaurant after getting a report of a man acting suspiciously.

Mangione allegedly gave officers a fake New Jersey ID, which has been linked to his movements in New York before Thompson’s killing, but eventually gave them his real name.

Officers found a gun and silencer, both of which had been 3D printed, in his backpack after taking him into custody, along with multiple rounds of ammunition, police said. The gun is “consistent” with the one used to kill Thompson, New York police have said.

As of Tuesday morning, there was no attorney of record for Mangione, who graduated in 2020 from the University of Pennsylvania with both a bachelor’s and a master’s degree.

— NBC News’ Tom Winter and WNBC’s Jonathan Dienst contributed reporting.