The people spoke with The Associated Press on condition of anonymity because they weren’t authorized to release information publicly.A courtroom had been set aside in a Manhattan federal courthouse for Mangione’s appearance and an overflow courtroom was designated as a location for people to watch the proceeding on video in the event there are more people than can fit in the courtroom.

It was writings laid bare in a notebook found in Luigi Mangione’s possession, authorities say, that would help investigators build the federal case against him – a well-planned homicide that involved weeks of stalking the movements of his alleged victim,

NBC News reported that Luigi Mangione, indicted in the killing of UnitedHealthcare CEO Brian Thompson, was transported to New York on Thursday (Dec. 19) after waiving his right to an extradition hearing.