The Italian police on Monday uncovered a fraud operation that doctored cheap oil to sell it as extra virgin olive oil, local media reported.

According to the reports, 17 people were put under investigation on fraud-related charges, and three commercial operations were brought under observation in the central regions of Tuscany, Emilia Romagna and Lazio.

Police confiscated 5,000 liters of counterfeit oil kept in silos, and other 2,500 liters in garages where the fraudulent oil was being bottled with an overall estimated market value of over 500,000 euro (630,000 U.S. dollars), local news agency Ansa said.

Some 73 kg of chlorophyll and four jars of beta-carotene intended to chemically doctor the low-grade sunflower oil were also seized.

Once doctored to give it color and flavor, the counterfeit product will be sold by producers for distribution to commercial operations, local police was quoted as saying.

A similar major operation conducted in southern Italy in 2008 led to the arrest of dozens of people and closure of a number of farms and plants.