Asian history buffs: ninja villages?

My global studies teacher (a well known head case) mentioned the other day that there were, in feudal Japan, hidden "ninja villages" of men and women who had ran away to escape the government.  Can anyone give me some sort of verification on this?

>>20
Actually it did happen, I lived in the next town over. Don't tell me you get all your news from "the media" and believe everything they say.