That sounds like a really major issue, but interestingly I couldn’t find anything when I googled “Africans harassing tourists” (and I mean literally nothing came up using that search phrase, so I changed it to “harassing tourists” Paris. Some websites (Daily Mail in 2014, TripAdvisor in 2013, some weird website called ETurboNews in 2014 and so on) report on Romas harassing and pickpocketing, but that’s all I could find. I’m sure I’m making a mistake or perhaps I’m not creative enough with the search terms, but maybe you could provide links to some serious and politically objective (or as objective as possible) reports?