The Pordenone unit of Italy's financial police said the website was so sophisticated, consisting of “very accurate graphic design”, that the network was able to dupe shoppers into believing they were buying from the real Prada website.
The merchandise was sold at the exact same retail price set by the fashion label, and used the usual payment systems and shipping channels, police added.
But the payments were instead credited to a bank account in Guangdong, China, and the counterfeit merchandise was dispatched from Hong Kong, meaning shoppers also had to pay customs charges to receive their goods.
The probe was launched at the request of Prada, which had received complaints from buyers about the customs charges.
The company, which reported a sharp fall in profit during the first nine months of last year on the back of weak demand from Asia, asked investigators to look into whether the merchandise was fake.
Police said that once received by the customer, it was fairly obvious that the products were not authentic.
The French woman, from the Loire region, allegedly registered the website in the Netherlands. The site was connected to server in England and also passed through France, police said.
Investigators are now trying to home in on others involved in the network.