Luigi Mangione, the suspect accused of murdering UnitedHealthcare CEO Brian Thompson in Manhattan on Dec. 4, pleaded not guilty in Manhattan criminal court Monday morning.

Mangione, 26, was indicted on 11 state charges, including first-degree murder, second-degree murder as a crime of terrorism and several weapons charges. If convicted of the most serious charge, he could face life in prison without parole.

Luigi Mangione enters the courtroom of the New York Criminal Court on Monday, December 23, 2024. Magnione is facing federal charges for the alleged murder of UnitedHealthcare CEO Brian Thompson earlier this month. (Rashid Umar Abassi for Fox News Digital)

The charges include one count of first-degree murder, a AI felony; two counts of second-degree murder, a felony of AI; two counts of second-degree possession of a firearm, a Class C felony; four counts of third-degree possession of a weapon, a Class D felony; one count of Criminal Possession of a Weapon in the Fourth Degree, a Class E felony; and one count of second-degree criminal possession of a forged instrument, a Class D felony.

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