Investigators know that a highly decorated Army soldier shot himself in the head inside a Tesla Cybertruck packed with fireworks just before it exploded outside Trump International Hotel in Las Vegas on New Year's Day,

Matthew Livelsberger -- the driver of the Tesla Cybertruck that exploded outside the Trump International Las Vegas Hotel -- died from a self-inflicted gunshot wound.

Officials identified a military ID and passport belonging to Matthew Alan Livelsberger inside the Tesla Cybertruck that exploded outside the Trump hotel in Las Vegas. Police say Livelsberger likely shot himself in the head before the blast.