I'll transcribe here the news as I heard on TV yesterday (Globo News).
Police was chasing a stolen car. They fired and hit a 17 year-old girl on her head, who died. A policeman came near the girl and kicked her to verify if she was 'really dead' and went away. Neighbours were outraged by the police action and went to the streets putting fire on and throwing rocks at buses. A message circulated through the neighbourhood promising one basic food package to those who would participate in the manifestation.