The man accused of killing UnitedHealthcare CEO Brian Thompson has been charged with first-degree murder in furtherance of terrorism, prosecutors said Tuesday.

Luigi Mangione, 26, is also charged with two counts of second-degree murder, including one described as killing as an act of terrorism, Manhattan District Attorney Alvin Bragg’s office said Tuesday.

He faces several counts of criminal possession of a weapon and one count of second-degree criminal possession of a forged instrument as well, according to the district attorney’s office.

The maximum penalty possible for first-degree murder and second-degree murder as an act of terrorism is life without parole, while the maximum penalty for second-degree murder is 25 years to life, Bragg said at a news conference.

“This was a frightening, well-planned, targeted murder that was intended to cause shock and attention and intimidation,” Bragg said. “It occurred in one of the most bustling parts of our city, threatening the safety of local residents and tourists alike, commuters and businesspeople just starting out on their day.”

Mangione already was charged with murder in the Dec. 4 killing of Brian Thompson, but the indictment could help move along procedural steps toward extraditing the suspect.

Mangione is scheduled to appear in court in Pennsylvania on Thursday morning, first for a preliminary hearing on the charges he faces in Pennsylvania and then for an extradition hearing, Bragg said.

"We have indications that the defendant may waive that hearing, in which case he'd be brought to New York forthwith," he said. "In any event, we have been preparing on parallel paths and before the hearing we'll send to the governor of the state of New York the paperwork that would be necessary if he does not waive during that hearing."

Mangione’s New York lawyer hasn’t commented on the case.

After days of intense police searches and publicity, Mangione was spotted at a McDonald’s in Altoona, Pennsylvania, and arrested. New York police officials have said Mangione was carrying the gun used to kill Thompson, a passport and various fake IDs, including one that the suspected shooter presented to check into a New York hostel.

Mangione was charged with Pennsylvania gun and forgery offenses and locked up there without bail. His Pennsylvania lawyer has questioned the evidence for the forgery charge and the legal grounding for the gun charge. The attorney also has said Mangione would fight extradition to New York.

Hours after his arrest, the Manhattan district attorney’s office filed paperwork charging him with murder and other offenses. The indictment builds on that paperwork.

Investigators’ working theory is that Mangione, an Ivy League computer science grad from a prominent Maryland family, was propelled by anger at the U.S. health care system. A law enforcement bulletin obtained by The Associated Press said that when arrested, he was carrying a handwritten letter that called health insurance companies “parasitic” and complained about corporate greed.

Mangione repeatedly posted on social media about how spinal surgery last year had eased his chronic back pain, encouraging people with similar conditions to speak up for themselves if told they just had to live with it.

In a Reddit post in late April, he advised someone with a back problem to seek additional opinions from surgeons and, if necessary, say the pain made it impossible to work.

“We live in a capitalist society,” Mangione wrote. “I’ve found that the medical industry responds to these key words far more urgently than you describing unbearable pain and how it’s impacting your quality of life.”

He was never a UnitedHealthcare client, according to the insurer.

Mangione apparently cut himself off from his family and close friends in recent months. His family reported him missing to San Francisco authorities in November.

Thompson, who grew up on a farm in small-town Iowa, was trained as an accountant. A married father of two high-schoolers, he had worked at the giant UnitedHealth Group for 20 years and became CEO of its insurance arm in 2021.

His killing kindled a fiery outpouring of resentment toward U.S. health insurance companies, as Americans swapped stories online and elsewhere of being denied coverage, left in limbo as doctors and insurers disagreed, and stuck with sizeable bills.

The shooting also rattled C-suites, as “wanted” posters with other health care executives’ names and faces appeared on New York streets and an outpouring of online vitriol prompted police to warn that there could be an “elevated threat.”