Please, lets remain truthful and not lie about facts on the ground to fit into our preconceived notions. The one article that everyone is sighting as proof of Islamic involvement was published in EARLY OCTOBER. The Muslims did have a march in October, which is what the chanting took place at. It is not connected with the anarchist riots going on now.
Here is pic from today's riots. There are lots of them out there. There is no visible Islamic component to the signs. This is the so-called black-block anarchists. They are a huge problem in Europe. This needs to be well understood by everyone at Free Republic.

Note: motorcycle helmet, man with video camera. Not penniless refugees and the don't look African or Middle Eastern.
I know these people. They are variously referred to as "anarchists" "black-block" "autonomous" and "anti-authoritarians". We have them in the USA too. They were the instigators at the Seattle riots a few years back.

They come ready to fight police, all in black, masked with motorcycle helmets.
Here is video, their anarchist banners (black and red) are clearly visible. The BBC reporter mentions that this is escalation of frequent clashes between anarchists and police; VIDEO
note: black & red flag in right background
note: worldwide anarchist symbol grafitti
Jack Black is 100% correct. Clashes between the police, anarchists and other radical youth groups in Greece and Europe in general are common. There is a longstanding, delicate co-existence between the police in Greece and groups of “anarchists” “black-block” “autonomous” and “anti-authoritarians” youths/adults tolerate certain crime in where many believe the authorities know who these individuals who organize such events are but won’t go after them because their ‘leaders’ are the children of the elite in Greece, i.e. bored rich kids with nothing to do, but this type of anarchism isn’t a Greek thing only, they are not some poor immigrant kids rioting. Such violent anarchists who clash with the police because they don’t believe in ‘authority’ are very common through out Europe and the world.