Can just anyone have a car towed?

My car broke down, and I am borrowing my friend's car for a couple of months until I can save up to fix mine. I live in a non-gated apartment complex, but up the hill from us are these really trashy looking duplexes. Well, one of my neighbors put a note on my car saying that "They know I don't live there" that "I live up the hill, and am just parking my car there." The note goes on to say that if they see my friend's car there again, they will have it towed. There are priority parkins for residents, and unmarked spots for everyone else. Since the car is actually my friend's and not mine, I have been parking it in the regular non-priority area. The note didn't leave a name or apartment number, and I have at least a couple of hundred neighbors, so I have no idea who left the note. I live there, this is the car I'm using for the next couple of months, and I don't have a choice but to use it. So it is going to be sitting out there, and the person said in their note that if they see it again, they will have it towed. Can just anyone have a car towed? I'm really worried, what can I do?