De Grisogono white gold necklace with white diamonds and black diamonds Biennale Paris

TO CATCH A THIEF: A thief made away with jewelry worth more than 5 million euros, or $5.3 million at current exchange, in what is being described as one of the most deftly executed heists ever staged in Paris.

Two rings and two loose diamonds were stolen on the morning of Dec. 30 at a showroom on Rue de la Boétie in the French capital’s tony 8th arrondissement, a spokesman for the Paris police said on Thursday. He confirmed the reported value of the loot but was unable to provide any additional details.

The thief posed as a potential client during a private appointment at the De Grisogono showroom, according to French media reports. Drawing comparisons with fictional French gentleman thief Arsène Lupin, daily newspaper Le Parisien said the suspect discreetly swapped the precious pieces for copies and left without anyone noticing what had happened.

The matter has been referred to the Paris public prosecutor. Officials at De Grisogono declined to comment.

If confirmed, it would not be the first time the Geneva-based jeweler has been targeted by thieves in France. In 2013, robbers made away with a high jewelry necklace worth 2 million euros, or around $2.6 million, at the house’s 20th anniversary party during the Cannes Film Festival, which drew guests including Sharon Stone.

The following year, two men held up the De Grisogono store on Rue Saint-Honoré in Paris in the latest of a spate of increasingly violent jewelry heists, including once incident in which a gang rammed a car into the window of a store.

As a result, jewelers on Place Vendôme and the surrounding area stepped up their security efforts and the police presence in the district was increased, resulting in a noticeable drop in thefts targeting stores. Thieves appear to be focusing instead on high-net-worth individuals like Kim Kardashian, who was tied up and locked in a bathroom while armed thieves made off with several million dollars’ worth of her jewelry during Paris Fashion Week.