Cybercrime requires such specialized skills that the Mafia is turning to freelance hackers and other IT experts "who promote their services on hidden websites" as reported by Paul Peachey for The Independent: "the high returns and relative low-risk of cybercrime has lured traditional criminal groups and spawned a service industry to feed it."
The hidden websites on the so-called dark net typically are accessed by the TorBrowser as reported by BBC News:
It allows people to use Tor, an "onion-routing" system that makes a PC's net address untraceable. It bounces encrypted data through several randomly selected computer servers on a volunteer network before it reaches its destination. There are also many hidden sites on the network ending in the dot-onion suffix, including drugs markets.
Last October the general public became aware of the dark net when the FBI took down the online forum Silk Road which allegedly was used by some as an underworld bazaar to peddle drugs and other illicit products and services in virtual anonymity, and arrested its founder Ross William Ulbricht who is accused of contracting for the murder of those who posed a threat to the site as reported by Andy Greenberg for Forbes.
The dark net also is used for the distribution of child porn by organized crime. For example, last June Italian authorities announced it had closed several child porn sites on the dark net which were operated by the 'Ndrangheta or Calabrian Mafia as reported by ANSA.