"Clever, pleasant and a bit of a loner, but certainly not a crazy guy," one of the 19-year-old's former classmates at Delft Technical University told the daily Algemeen Dagblad.
Another former classmate told the NOS public broadcaster, where the drama played off, that the teen, seemingly normal, had a rich imagination and was "often in his own world."
"In recent years he was interested in conspiracy theories involving the Free Masons and a 'new world order'," the student said.
The man, a first-year student at Delft Technical University, forced his way into a studio at the NOS broadcaster's headquarters in the city of Hilversum Thursday evening waving what turned out to be a fake pistol and demanding airtime.
He claimed to represent a hackers' collective.
He was quickly overpowered by police and offered no resistance.