In Athens, the police patrols are mostly located around Exarchia, the anarchist neighborhood. The Police station around the neighborhood constantly for many years. Usually nothing happens but occasionally police received the green light to go and find an 'anarchist', you should better not be around during one of these cops raids. You should also take care during the demonstrations, the greeks cops can be really ruthless.
A normal day in Athens, an army of cops guarding the parliament because people
are demonstrating on Syntagma, while the upper class is enjoying expansive lunch
at the terraces of the Kolonaki's restaurants.