Greek anarchists smashed windows at the French Institutes in Athens and Salonica in order to show their "solidarity"
with the French rioters. When the cops came after them, they sought shelter in the university where police are barred from entering. I'm willing to bet money that none of these guys was an Arab, a Muslim or a descendant of North African immigrants, they're all just plain Greek. And I don't know what sort of solidarity they hoped to show other than their solidarity for stupidity and violence.