Via The Guardian:
A protest in support of striking teachers ended in dozens of arrests in Rio de Janeiro on Tuesday night as the annual 15 October Teachers’ Day holiday came to a violent conclusion. A police car was set on fire, bank foyers and cash machines smashed and fires lit in Floriano Square after thousands joined an action that brought the city centre to a standstill.
Police used teargas and percussion grenades as they struggled to regain control of the city centre from a crowd including black-clad masked youths linked to the Black Bloc protest movement.
Some protesters threw rocks, fireworks and other missiles – advancing across Floriano Square behind sheets of corrugated iron and forcing riot police to retreat at one point.
Police, who were evident in much smaller numbers, also threw rocks at protesters. Adolfo Tavares, 28, was treated by volunteer medics after he said he was hit in the leg by a rock thrown by police. “Police formed a barrier and began throwing rocks,” he said.