Not that many Nigerians in Calabria.
Catania and Castel Volturno is a different story. They're around, but they stick to pimping and retail level drug dealing. No use in believing the sensationalist newspapers. Give it 5-10 years and Nigerian crime in Italy will barely be a point of conversation anymore.
it depends on the politicians, the right wind ones (berlusconi, salvini etc.) love to blame some immigrant group to get more votes and the media tends to overrate them or even invent something, for example the murder of that girl has absolutely nothing to do with nigerian organized crime, they probably never carried out a single murder in italy... most serious info about them come from DIA reports that have not any interest to overrate anybody, in the DIA report you find over 350 pages about italian organized crime groups and only 5 about nigerians (10 about foreign gangs as a whole), that's thre real picture and threats of organized crime in italy
