Were the agents in "Final Destination" somewhat mysterious and surreal?

I understand that in the real world, predicting something bad and then it happening can be somewhat unusual behavior and can get a person to be considered a person of interest. But it seemed like the agents, maybe moreso Schreck than Weine, were toying with him, instead of downright being straight on what they suspected Alex of doing. Last time I checked, you can’t exactly be arrested for someone predicting that something bad would happen and it coming true (because in itself that’s not a crime, and that’s not evidence someone did something; clearly Alex was not acting suspicious whatsoever, he didn’t have bombs; he was with his friends the whole time, and everyone of their testimonies afterwards clears Alex of wrongdoing). The way they were acting was mysterious, as though they were men in black of some sort.
I mean were they agents of the underworld or something? Cause they were playing mind games with Alex