The PKK aka Kurdistan Worker's Party are extremists
in the sense that they are Communists, who are all extremists. I have never met a commie and I've met plenty) who wasn't certifiably insane, in that everything he or she steadfastly believed to be true had already been proven to be false over and over again.
They are like adults who still believes in Santa Claus, even though they haven't gotten any toys for the last 50 years.
The problem is this, the media yammers on and on about the PKK extremists without once mentioning that they are Communists. God forbid that you should call a spade a spade. Maoist rebels, the PKK, the Shining Path, are all murdering, commie thug bastards.