HOLLIDAYSBURG, Pa. – Luigi Mangione, the man charged with murder in the death of UnitedHealthcare CEO Brian Thompson, broke his day of silence with an outburst as he was escorted into a Pennsylvania courthouse, where he challenged his arrest.

"It's completely out of touch, and an insult to the intelligence of the American people and its lived experience," Mangione shouted, prompting his detail of about 10 officers to hurry him inside. 

Dressed in an orange jumpsuit, Mangione appeared unfazed. He was seen whispering with his attorney, Thomas Dickey, glancing at reporters and mumbling to himself at the Blair County Court hearing around 2 p.m.

Prosecutors say he had $8,000 U.S. cash; $2,000 foreign cash; masks, and a passport on him – in addition to a "ghost gun" with a silencer resembling the weapon used to kill Thompson – when he was apprehended by police in Altoona on Monday.

SUSPECTED UNITEDHEALTHCARE CEO KILLER LUIGI MANGIONE MUGSHOT RELEASED

Dickey argued that his client had masks because "some people still have the COVID fear."

The 26-year-old was denied bail and will remain incarcerated at SCI Huntingdon until his attorney files a writ of habeas corpus, challenging whether he is being lawfully detained.

Mangione's attorneys now have 14 days to file the document. Shortly after the hearing, Blair County District Attorney Peter Weeks said that Mangione's New York charges "take precedent" over those in Pennsylvania, and that his office will do whatever they can to facilitate the suspect's extradition.

Manhattan District Attorney Alvin Bragg said on Tuesday that his office may seek a governor's warrant to extradite Mangione's return to New York, which would take 30 days.

Mangione was taken into custody after he was recognized by an observant patron at an area McDonald's around 9:15 a.m. Monday. The Ivy League-educated software engineer refused to speak with investigators on Monday, and was placed in a holding cell after hours of attempted questioning. 

UNITEDHEALTHCARE CEO MURDER SUSPECT LUIGI MANGIONE LIVE BLOG

Luigi Mangione pictured in a Pennsylvania mugshot after his arrest in connection with the murder of UnitedHealthcare CEO Brian Thompson.

Luigi Mangione pictured in a Pennsylvania mugshot after his arrest in connection with the murder of UnitedHealthcare CEO Brian Thompson. (Obtained by Fox News Digital)

He was arraigned in Blair County Court on a forgery charge on Monday night; New York prosecutors have charged him with second-degree murder, second-degree criminal possession of a weapon (loaded firearm), second-degree possession of a forged instrument and third-degree criminal possession of a weapon (firearm silencer) in Thompson's Dec. 4 shooting death.

NYPD officials arrived at the Altoona Police Department several hours after Mangione was taken into custody on Monday. Sources with the NYPD told Fox News Digital that the suspect was not disorderly during his first day in custody and that his demeanor changed overnight.

WHO IS LUIGI MANGIONE, SUSPECT IN UNITEDHEALTHCARE CEO MURDER?

Mangione's arrest came after a five-day nationwide manhunt involving the FBI and police departments in multiple states. 

WATCH: McDonald's customer recognized suspect's backpack, jacket

He reportedly had a manifesto on his person when he was arrested that enumerated his grievances with the healthcare industry.

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After attending a $40,000-per-year private school, the Gilman School in Baltimore, Mangione graduated from the University of Pennsylvania with bachelor and master's degrees in engineering and was part of the Eta Kappa Nu Honor Society for Electrical and Computer Engineering.