With the Rio Olympics less than a year away, violence on the city's streets has - once again - come into sharp focus.
Clashes between police and drugs gangs have intensified following the killing of 17 year-old Eduardo Victor.
Five military policemen have been arrested after video emerged which appeared to show the officers doctoring the crime scene, and placing a gun in the dead teenager's hand.
The BBC's Wyre Davies reports.
Eduardo Felipe Santos Victor was just 17-years-old