Beware: there might be a serial thief on the loose at Cannes. After a million in Chopard jewelry was reported stolen just last week, Reuters reports that this Thursday there was an even bolder theft – a diamond necklace, reportedly worth 2 million euros (or just about $2.6 million). This time, the piece was part of a collection by De Grisogono, an upmarket Swiss jeweler.

Fawaz Gruosi, the founder of the company, explained that the piece was part of an extremely valuable collection, which was displayed at the Hotel Du Cap-Eden-Roc in Antibes outside Cannes on Tuesday night. Unlike the stolen Chopard pieces, the necklace wasn’t intended for a celebrity or the red carpet of a Cannes premiere, however Sharon Stone and Paris Hilton were among the guests at the glitzy event, where the necklace was displayed.

The necklace, as well as the other pieces, were heavily guarded, with 80 security guards on duty that night, as well as local police, hotel security, and De Grisogono staff. Obviously, the police are baffled, but they’re doing everything they can to retrieve the stolen jewels. "We don't know exactly what happened ... it was one of the most beautiful items we had," Gruosi told Reuters Television. "The police are trying to figure out what happened."

Meanwhile, some clever thieves have suddenly found themselves overnight millionaires. Apparently this isn’t just the stuff of Hollywood films after all, although apparently the having a few world-famous stars about brings out the best in some thieves.

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Paris Hilton