A 26-year-old man who was apprehended in McDonald’s has been charged with murder over the shooting death of a UnitedHealthcare insurance CEO, according to media reports.

Luigi Mangione was taken into custody on Tuesday (AEDT) and was denied bail when he appeared in a Pennsylvania court.

He was initially held on five charges, including carrying an unlicensed firearm and forgery, after he was picked up with a gun and fake IDs.

US media report he has since been charged with murder.

Chilling details about Mangione emerged as his mugshot was released and circulated around the world.

The suspect was captured in Altoona, Pennsylvania, after a McDonald’s worker recognised him as the man sought over the death of UnitedHealth executive Brian Thompson.

The worker called local police, who said they found a man “wearing a medical mask and a beanie” and sitting “in the rear of the building at a table”, looking at a laptop, according to a criminal complaint read out in court.

Officers asked the man to pull down the mask – and “immediately recognised him as the suspect”.

The man gave the police a New Jersey ID in the name of Mark Rosario. When they asked him if he had been to New York City recently, he “became quiet and started to shake”, the complaint said.

After a search turned up no one of that name, the man told officers he was Luigi Mangione. Asked why he gave a false name, he said “I clearly shouldn’t have”, according to the complaint.

Mangione was found with a “ghost gun” – a firearm assembled from parts, making it untraceable – and a silencer consistent with the weapon used to shoot Thompson, New York City Police Commissioner Jessica Tisch said.

He also had clothing and a mask similar to those worn by the killer. The ghost gun may have been produced by a 3D printer, said Joseph Kenny, the NYPD’s chief of detectives.

Police also found a handwritten document that speaks to “both his motivation and his mindset”, Tisch said. While the document did not mention specific targets, Mangione harboured “ill will toward corporate America”, Kenny said.

“These parasites had it coming,” one line from the note reads, according to CNN.

“I do apologise for any strife and trauma, but it had to be done,” another states.

A Goodreads account apparently belonging to Mangione also gave a four-star review earlier this year to a book written by Unabomber Ted Kaczynski earlier this year, according to The New York Times.

Kaczynski was a Chicago-born mathematician and domestic terrorist whose mail bombing campaign killed three people and injured more than two dozen others during the late 1970s and early 90s.

“It’s easy to quickly and thoughtlessly write this off as the manifesto of a lunatic, in order to avoid facing some of the uncomfortable problems it identifies,” the review reads.

“But it’s simply impossible to ignore how prescient many of his predictions about modern society turned out.”

Mangione appeared in court briefly on Tuesday (Australian time), on firearms charges. He was remanded without bail.

He is next due in court in Pennsylvania on December 23, ahead of a likely bid to extradite him to New York.

What we know about suspect

Mangione graduated from a private all-boys school in Baltimore as valedictorian in 2016 before earning dual engineering degrees at the University of Pennsylvania, according to media reports, social media posts and school records.

His last known address was in Honolulu, officials said.

Thompson, 50, was gunned down outside a Manhattan hotel early on Wednesday (local time) by a masked man who appeared to wait for his arrival before shooting the executive from behind.

The suspect ran from the scene and then rode a bike into Central Park. Surveillance video captured him exiting the park and taking a taxi to a bus station in northern Manhattan, where police believe he used a bus to flee the city.

Police said Thompson appeared to be deliberately targeted.

The words “deny,” “defend” and “depose” were carved into shell casings found at the scene, several news outlets have reported. The words evoke the title of a book critical of the insurance industry published in 2010 titled Delay, Deny, Defend: Why Insurance Companies Don’t Pay Claims and What You Can Do About It.

Mangione graduated from the University of Pennsylvania in 2020 with bachelor’s and master’s degrees in engineering, according to a commencement program.

A Facebook profile that appears to belong to Mangione identified him as a native of Towson, Maryland, and a former student at the University of Pennsylvania. Photos appear to show Mangione at Stanford University wearing Stanford-branded clothing.

Neither university immediately responded to requests for comment.

An X account that appears to be owned by Mangione says he has an MSE and BSE. in computer science from the University of Pennsylvania and lives in Honolulu, Hawaii.

Thompson, a father of two, had been CEO of UnitedHealth Group’s insurance unit since April 2021, part of a 20-year career with the company. He was in New York to attend the company’s annual investor conference.

“Our hope is that today’s apprehension brings some relief to Brian’s family, friends, colleagues and the many others affected by this unspeakable tragedy,” a spokesperson for UnitedHealth said.

-with AAP