Recent and archive images of “cracklands” across Brazil. Swarms of crack users have converted entire swaths of central neighborhoods into nocturnal encampments doubling as open-air crack marketplaces.

Demand for cocaine has soared along with the economy over the past decade and fueled an abundant supply of crack now ensnaring thousands of new addicts. Legions of the addicted roam city centers across Brazil, many of them venues chosen to showcase Brazil's ascendance during the 2014 World Cup of soccer and the Olympic Games in 2016.

These images reflect what sociologists, health experts and law enforcement officials say is a rapidly growing problem that puts Brazil squarely in the center of the international drug trade. Demand for cocaine has grown among Brazilians, and in recent years the country has become a crucial path for transit of the drug as it travels from source countries in the Andes to markets in Europe and beyond.

Because of the rapid, but brief high - and crack's highly addictive nature - addicts sometimes smoke more than a dozen times a day. Though an individual hit is cheap, about the price of a candy bar, long-time users say they are willing to lose everything in exchange for another high.