Luigi Mangione, the suspect accused of gunning down UnitedHealthcare CEO Brian Thompson, left New York City by train, and not by bus as first thought, police sources told ABC News. At first, investigators believed Mangione had boarded a bus at the Port Authority terminal by the George Washington Bridge,

Luigi Mangione is believed to be a person of interest in last week's deadly shooting of UnitedHealthcare CEO Brian Thompson, police said Monday. The 26-year-old was arrested on firearms charges in Pennsylvania, where New York police detectives were heading to interview him amid a massive manhunt for the shooter.