[mynameishere]

What an odd "problem". I would expect the librarian to call the police. And if there was a "trained security guard" on the premises I would expect him to also call the police.

(That's why we have police.)

[dazc]

Clearly you haven't encountered the Police in the UK. Unless it's a life or death emergency situation the default response is often one of disinterest.

[the-red-herring]

Well, you can't rely on police for everything. I mean, they aren't your personal dobermen.