Criminals in Brazil only strike when there are no people around.
Be extra careful with laptops, carry-on-luggage, and briefcases for these are targeted.
Here are two very useful articles published by the US State department.
These criminals—who also troll social media sites and chat rooms in search of romantic victims—usually claim to be Americans traveling or working abroad. While their most common targets are women over 40 who are divorced, widowed, and/or disabled, but every age group and demographic is at risk. You’re contacted online by someone who appears interested in you.