The average witness wouldn't know a "machine gun" from a French stick.
As to the media they're as bad. Even the "Crime Correspondents" don't understand the different between Automatic and Semi-automatic. Or if they do use the term "automatic" inaccurately so as to sex up their piece.
As the guy is reported to have had three out of the five firearms allowed to the average Joe by Dutch Law, it is unlikely that he had a legal full auto weapon.
Apparently he had come to the notice of the Dutch Fuzz for firearms infractions recently. Maybe he was doing a Thomas Hamilton. That to say, commit an act so bad that legal firearms owners will get the blame and have their firearms confiscated. Which is one of the generally accepted theories about Dunblane.