They are making it up. “Shouted threats” reported by print media were investigated by the proper authorities, and nobody had heard them but the reporter. Nothing but lies.
Of course, it got re-reported ad nauseum anyway.
If they had a video or recording of such behaviour, it would be on every MSM network news show.
Funny how the Left gets to make movies and write novels portraying the assassination of Dubya, but we get tarred and feathered if one guy has an outburst at a rally. Even if the story of "kill him" were true it would be pathetic.