(ANSA) - Rome, October 4 - Six tonnes of fake Sorrento lemons for sale in Naples were picked up in a nationwide police sweep Thursday that netted 3,500 kilograms of mislabelled food. The lemons, which actually came from Argentina, were part a crackdown on food fraud across the country. Police in Macerata confiscated 1,300 kilograms of pizzas falsely claiming to have red onion from the town of Tropea and tomatos from San Marzano. Police said they were also investigating rackets for selling fake food abroad. So far they have uncovered kits used to produce counterfeit wines such as Barolo, Chianti, Valpolicella, Montepulciano and Nero d'Avola, police said.