Police said Luigi Mangione, the man charged in the killing of UnitedHealthcare CEO Brian Thompson, appears to have had a ghost gun, a weapon that can be made using a 3D printer.

He was in possession of a ghost gun that had the capability of firing a nine millimeter round and a suppressor,” NYPD Commissioner Jessica Tisch said at a Monday press briefing, adding that

Brian Thompson was laid to rest at a private funeral service in his Minnesota hometown on Monday. That same day, Luigi Mangione was arrested in Pennsylvania and charged with murder in connection to the UnitedHealthcare CEO’s death.