Drugs war in Rio de Janeiro, Brazil

Police personnel from a tactical unit take positions at one of the entrances to the Morro dos Macacos shantytown Photograph: Helio Cardoso/AFP/Getty Images

A bus burns in a street Photograph: Miguel Fernandez/EPA

An armoured police vehicle near two public buses set on fire by drug gangs trying to distract the police from their battle for the control of a slum Photograph: Ricardo Moraes/Reuters

A couple carrying a child leaving the Macacos slum Photograph: Felipe Dana/AP

Firefighters work on two buses set on fire by drug dealers at Morro dos Macacos shantytown Photograph: Helio Cardoso/AFP/Getty Images

Police officers extinguish a fire from the wreckage of a police helicopter Photograph: Alexandre Brum/AP

The remains of a police helicopter shot down by drug dealers Photograph: Helio Cardoso/AFP/Getty Images

Firefighters throw water to the remains of a police helicopter Photograph: Felipe Dana/AP

Police officers show bullet capsules found at the slum Photograph: Felipe Dana/AP

Maria da Costa Gomes, bottom left, mourns over the covered body of her son Marcelo, killed during a police operation at the Morro dos Macacos slum Photograph: Andre Mourao/AP