Sorry to say this, I had done this before - psychological harassment. I drive that f88king moron up the wall, get fired whenever he started on a new job. I sent "love letters" to his employers. When you are an employee, you will be screwed if you misbehave. Your personal information is with the HR Dept. and you can be tracked especially if you remain in the same industry. Singapore is a f88king small place.
What did he do ? As an employee, he spread rumors about the company and in cohort with some employees of our suppliers to influence our customers into believing his stories. Because of him, we had to work extra hard to retain our customers and to find out who is behind all the rumors as well as coaxing all the parties to reveal who spread the rumors. With all evidence pointing to this employee, we fired him in a nice way and screwed his arse HARD !!
For your case, I do not know what you have done. Unless you have done things that are so detrimental to the company or caused the company to suffer great financial loss, where such treatments are meted out to you.
Even as bosses and in business world, it is better to keep political opinions to yourself. Some arseholes out there are grassroot leaders, they will sabo you if your opinions antagonize them. Some of these arseholes pretend to be opposition supporters even though they are pappy, to entice you to speak up. When you speak up your opinions, you really ask for it !!!
Yours is more of commercial reasons,as for mine,it's more of my big mouth when I was in reservist,there is no financial loss at all. As I saw it,it was a huge thing then. You are right,I have encountered these assholes, very good enticers, as i was quite talkative and having a loose gap,I will tell them what i knew very easily. to make things worse,shortly after the incident,i seem to appear at the wrong place at the wrong time. There is this minister who gave me a kind of hostile look and i don;t even know or how did i offend him. after sometime,I observed from TV and newspaper,i conclude that he is a very cunning person. If he read this,he will know who I am.