Due to Manaus's link by boat with Colombia, drugs is a growing problem. When I spoke to soem of the people in Manaus they simply said it is part of the economy: the poor sell drugs to the poorer. There is no security on boats not on the border so drugs flow easily into Manaus. When I was here a 75 year-old grandmother was caught with 15Kilos of Cocaine. This is extemely sad and greatly increases crime in Manaus, espacially in the favelas (or slums). Be careful, drugs lead to a high crime rate.Try to avoid confrontations with drug infested areas or people, and don't even enter the drug favelas (the different color houses represents the different drugs they sell).