Policemen patrol next to a wall being built by Rio de Janeiro city hall to limit the expansion of the Dona Marta slum from encroaching on the forest in Rio de Janeiro May 29, 2009.REUTERS/Sergio Moraes
Policemen patrol next to a wall being built by Rio de Janeiro city hall to limit the expansion of the Dona Marta slum from encroaching on the forest in Rio de Janeiro May 29, 2009.