A supermarket trolley stuffed with a mutilated corpse, a row of burning buses and a police helicopter lying in tatters on a football pitch were, not surprisingly, the sort of images that were absent from Rio de Janeiro’s candidate file when it applied to host the 2016 Olympics.

But it was these pictures that were splashed across the world’s newspapers and television screens last month, after police clashed with drug traffickers in Rio’s Morro dos Macacos favela. The battles that followed left more than 40 dead, only two weeks after Rio was named as the first South American city to host the Olympic Games.