Police operation in the University of Athens

ATHENS, GREECE - APRIL 17: Workers take down a banner from the main building of the University of Athens after riot policemen entered the building to detain a group called themselves as 'anarchists' who have occupied the area for more than two weeks in support of hunger strikers in Greek prisons, in Athens, Greece, 17 April 2015. Prisoners convicted for participation in urban guerilla groups have been on hunger strike for more than forty days demanding the abolition of maximum security C-type prisons (Photo by Ayhan Mehmet/Anadolu Agency/Getty Images)