Organized crime groups "have taken advantage of the economic crisis to infiltrate the legal economy in an increasingly vast and widespread manner," Coldiretti said on Sunday.
Their warning followed a vast anti-mafia sting over the weekend, which uncovered links between popular tourist restaurants and organized crime groups.
Police seized the bank accounts and 24 properties of a Neapolitan family, amounting to a total value of 20 million euros.
One of the restaurants was Donna Sophia dal 1931, located in central Milan between the city's cathedral and canals. On TripAdvisor, the eatery had received mixed reviews, with some guests criticizing the food and service and others complimenting the "delicious Neapolitan pizza".
The group was also found to be behind Villa delle Ninfe, an event venue and restaurant in Pozzuoli, Naples.
The use of restaurants as a screen for illegal activities is nothing new; in 2015, two well-known Rome restaurants were shut down over links to criminal groups, and the Calabria-based 'Ndrangheta were even found to be behind a popular New York pizzeria.
But Coldiretti said that the practice is becoming increasingly widespread, with criminals often cutting corners in health and safety which put consumers and the environment at risk.
Agricultural crime or 'agromafie' brought in a massive 21.8 billion euros for underground groups last year, according to Coldiretti figures. This represents a 30 percent increase from the previous year, with mafia groups infiltrating all kinds of food businesses, from trendy bars to restaurants and chains, and even food production.
Criminal bosses use extortion to force farmers to sell at low prices and businesses to buy their products, creating monopolies.
"Agriculture has become one of the priority investment areas for the underworld," Coldiretti explained. "They understand that it is strategic in a time of crisis because it allows them to infiltrate civil society in a widespread way and condition people's everyday lives."
However, restaurants are far from the only legitimate businesses used as a screen for illegal activities by mafia groups.
Clan members are able to launder money gained through drug trafficking or other crimes using businesses ranging from souvenir shops to real estate.
Organized crime groups were also found to have exploited the migrant crisis, setting up illegal accommodation centres with sub-standard conditions, to make money off the new arrivals to Italy. And prosecutors have warned of mafia infiltration in the renewable energy sector, meaning poorer regions such as Sardinia and Sicily have seen little of the economic benefits from Italy's green energy boom.
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