The Schaffhausen cantonal police found that illicit traders had smuggled some 230 puppies into Switzerland, 130 of which were brought in by one Hungarian woman, newspaper Neue Zürcher Zeitung reports.

This is the biggest case of illegal dog trading that the Swiss customs have ever had to deal with.

The majority of the smuggled puppies were Chihuahuas, and were taken into Switzerland via St. Gallen. Despite the fact that the dogs had not been to the vets and were not vaccinated, the Hungarian trader nevertheless managed to sell the puppies for a total of around 100,000 francs ($102,311).

The Chihuahua’s popularity has risen dramatically in recent years after the dogs were catapulted into the limelight by people like Paris Hilton, who famously carries one around in a purse.

“The puppies from Eastern Europe often grow up in miserable conditions and are taken away from their mothers much too early,” Denise Delley of the Swiss animal registration service (ANIS) told the 20 Minuten news site.

Often these animals have diseases or develop other illnesses, resulting in high veterinary costs, she added.

The Hungarian woman’s middleman is now also being investigated. He sold the animals on for approximately 850 francs ($ 868) apiece without a permit. A fully certified purebred Chihuahua can cost in the region of 2,500 francs ($ 2,554).