According to Italian daily Corriere della Sera, those arrested in Turin are part of two separate criminal gangs which are also held responsible for 19 burglaries.
The robbers allegedly threatened jewellery shop assistants as well as staff in supermarkets, pharmacies, travel agents and other shops with guns before robbing them.
During the investigation, which began in 2010, police seized 70 kilos of drugs. Fifty-nine people had already been arrested.
In a video released by Italian police (below), alleged gang members are seen threatening staff in shops with guns before demanding money.