Accused United Healthcare CEO killer Mangione pleads not guilty to state terror and murder charges

The healthcare CEO shooting suspect, Luigi Mangione, pleaded not guilty to New York state murder and terror charges during a court appearance on Monday. 

Mangione was indicted by a New York grand jury last week in the killing of UnitedHealthcare CEO Brian Thompson in Manhattan.

Mangione faces murder charges in both New York and Pennsylvania, where he was caught. He also faces criminal charges in New York for possession and building of a weapon and killing in the act of terrorism. 

Federal prosecutors also charged Mangione with murder, stalking, and a firearms offense. If convicted of the federal murder charge, he could face the death penalty.