Very shortly after the event, I remember one or two news reports saying the rifle was left in the car. All later reports I saw were that a rifle was used.
News organizations sometimes get information wrong when they're rushing to report on an event. That's not evidence of a lie or of a conspiracy.
“Compleχity is a symptom of confusion, not a cause.” —Jeff Hawkins
“The egg hatched...” “...the egg hatched... and a hundred baby spiders came out...”