ATHENS, Greece — Masked youths hurled firebombs and chunks of marble at police during a march in Athens Sunday to mark the first anniversary of the police shooting of a teen whose death sparked massive riots.
Police fired volleys of tear gas to disperse the youths in running street battles in the center of the capital as several thousand demonstrators commemorated the death of 15-year-old Alexandros Grigoropoulos. It sent youths rampaging through cities for two weeks last December.
On Sunday, the rioters smashed bank windows, overturned trash bins and set them alight as they hurled rocks and fire crackers at riot police. Authorities said 177 people were detained for public order offenses in Athens and another 103 in the northern city of Thessaloniki, where a similar demonstration turned violent. Police also clashed with protesters in the southern city of Patras and the northwestern city of Ioannina.
At least five protesters and 16 police were injured in the violence, police said.
Police on motorcycles chased rioters amid scenes of chaos at Athens' main Syntagma Square, with youths punching and kicking officers pushed off their bikes.
At Athens University, masked protesters broke into the building and pulled down a Greek flag, replacing it with a black-and-red anarchist banner.
Authorities said the dean was injured when the youths broke into the building, and he was hospitalized in an intensive care unit.
As night fell, about 200 masked demonstrators were holed up in the neoclassical university building, smashing marble chunks off the university steps and ripping up paving stones from the courtyard to use as missiles against the police, before eventually leaving the building.
Clashes between demonstrators and police continued late into the night at another campus building, the Athens Polytechnic.
More than 6,000 police had been deployed across Athens in an effort to prevent violence.