Thieves outsmarted 80 security guards in an exclusive French Riviera hotel and made off with a necklace that creators say is worth $2.6 million on Tuesday, according to The New York Post.

This was  second major jewelry heist during this year's Cannes Film Festival.

The De Grisogono jewelry house announced the theft Thursday and said the necklace was stolen after a party for festival guests at the Hôtel du Cap-Eden-Roc, located in the luxurious resort town of Cap d'Antibes, on Tuesday night.

In a statement, the company said the theft occurred "despite the large security measures set in place."

De Grisogono director Fawaz Gruosi said in the statement, "it is actually the first time it has happened in our 20-year history."

A police official said Thursday that the "high value" necklace was stolen overnight. She gave no further details and spoke chose to keep her anonymity because she was not authorized to speak on the record about an ongoing investigation.

Cap d'Antibes is just down the coast from Cannes and even more exclusive. The Hôtel du Cap-Eden-Roc often plays host to events during the festival.

Tuesday night's party included stars such as Sharon Stone, Ornella Mutti and others. The hotel hosted another party on Thursday night.

Last week, thieves stole about $1 million worth of jewels when they took a safe from the wall of a Novitel hotel room in Cannes. The room was being occupied by an employee of Chopard, the Swiss-based watch and jewelry maker that has loaned jewelry to celebrities who walk the red carpet at the film festival.