A Greek prosecutor charged seven people with fraudulently selling large quantities of adulterated sunflower oil as olive oil in Greece and abroad.
The seven, a family of four and three of their relatives, were also charged with forming a criminal gang, defrauding the state, falsifying documents and money laundering. They will face an examining magistrate later in the week, the prosecutor's office said.
The seven were arrested near the city of Larissa, in the Greek province of Thessaly, about 95 miles south of the northern Greek city of Thessaloniki, by the financial crimes squad of northern Greek police.
They were found operating a workshop where they added a dye to turn the yellow sunflower seed oil into a green hue resembling olive oil.
The adulterated oil was sold in five-litre cans to Greek consumers and exported, mainly to Germany.
Police found on the premises five tons of adulterated oil ready for packaging and 12 pallets ready for export. They also found a fleet of luxury cars.
Police first became aware of the widespread sale of adulterated oil about two years ago. Police say the adulterated oil was exported, to EU countries, using invoices that were later destroyed.