More than 500kg of cocaine was intercepted by Swiss authorities from a shipment of coffee beans transported to a Nespresso factory.

Workers at the Romont facility in the western Swiss canton of Fribourg notified authorities about a peculiar white substance found in sacks of coffee beans, according to police.

Staff at the Nestlé-owned coffee capsule manufacturer "discovered an unidentified white substance as they unloaded the freshly supplied bags of coffee beans," Fribourg police said on Thursday.

The drug was determined to be cocaine after police analyzed the material. Police stated that a search of five cargo containers "sent the same day by rail allowed for the capture of more than 500kg of this substance."

During the operation, police said they built up a massive security perimeter around the plant, which also included a big detachment of customs officers.

The units holding the pharmaceuticals were isolated, and the substance did not infect the plant's production, according to the statement.

According to authorities, the shipment originated in Brazil, and the seized cocaine was proven to be more than 80% pure, with an estimated street value of more than 50 million Swiss francs ($51 million).

“It appears that all of the drugs were destined for the European market,” police said.