Luigi Mangione, the suspect in the murder of the CEO of UnitedHealth, appeared in court in New York Crime News

Mangione faces new federal charges that carry the possibility of the death penalty in the United States.

Luigi Mangione, the suspect in the slaying of UnitedHealthcare CEO Brian Thompson, appeared in a New York court to face new federal charges, including murder and stalking.

Mangione’s arraignment on Thursday came after he was transferred from Pennsylvania to New York after he waived extradition proceedings.

Mangione, wearing a blue sweater and beige pants with ankle shackles, said little during his 15-minute appearance before U.S. Magistrate Judge Katharine Parker in Manhattan.

The 26-year-old Ivy League graduate, who already faces several state charges, was charged with murder with a firearm, two counts of stalking and illegal use of a gun silencer, according to an unsealed criminal complaint.

The federal charges raised the possibility that Mangione could face the death penalty if prosecutors seek it.

Mangione’s attorney, Karen Friedman Agnifilo, said it was “a very unusual situation” for a defendant to face concurrent state and federal cases.

“Frankly, I’ve never seen anything like what happened here,” Friedman Agnifilo said.

According to the criminal complaint, Mangione traveled from Georgia to New York “for the purpose of stalking and killing Brian Thompson.”

A notebook found in Mangione’s possession after his arrest at a McDonald’s in Altoona, Pennsylvania, contained several handwritten pages “expressing hostility toward the health insurance industry and particularly wealthy executives,” according to the complaint.

An entry in August said the “target is insurance” because it “checks every box,” according to the complaint, while an entry in October described an intent to “confuse” an insurance company CEO.

Police said the words “delay,” “deny” and “deposit” were scrawled on shell casings found at the crime scene, a phrase used to describe insurer tactics to avoid paying claims.

As Mangione was arraigned, supporters gathered outside holding signs reading “Health over wealth” and “Luigi set us free.”

James Dennehy of the FBI’s New York Field Office said Magione’s alleged actions were “a carefully planned and targeted execution.”

“This alleged conspiracy demonstrates a heroic attitude toward humanity — regarding murder as an appropriate means of venting personal grievances,” Dennehy said.