It does not really matter what country you are in the threat of gang violence and harassment is always going to be a possibility. Especially in big cities where these massive games are held. These are prime targets for thieves and this is their Black Friday and they are just cashing in.
Yes, it saddens me to say that some of the gangs in Rio will try to take advantage of the international athletes and their supporters who are arriving from all around the world. Gangs are opportunist and have their own agenda. They will not stop hurting others just because the eyes of the world are watching.
Crime is a big problem in Brazil, and international sportsmen and women are prime targets. In most cases they have more money than Brazilains, they have little knowledge of the area and the language, and in most cases do not have the money to be well protected and well guarded.
The Olympics draw thousands of talented athletes from around the globe and even millions more watching from home to cheer on their respective country. Brazilian gangs thrive on public influence and are looking for an audience to incite fear into. The Olympic games are the perfect platform for such a spectacle. The athletes will most likely not be the targets but the high ranking diplomats that accompany them from each country are another story.