AP
Model Cara Delivigne, wearing a necklace by Chopard, arrives for opening ceremony and the screening of The Great Gatsby at the 66th international film festival, in
The hotel, located on the exclusive Promenade de la Croisette, was hosting a summer jewelry exhibit from the prestigious Leviev diamond house, which is owned by Israeli billionaire Lev Leviev.
Local media reported that the robber carried the jewels away in a briefcase shortly before noon.
"A full an urgent operation is under way to catch the culprit and recover these jewels," a Cannes police spokesman said. "Thieves see Cannes as rich pickings."
In May, during the famous Cannes Film Festival, thieves took about $1 million in jewels was stolen from a hotel room and a necklace worth $2.6 million from a hotel party.
Coincidentally, a Bosnian from the 'Pink Panther' gang of international jewel thieves escaped from a Swiss prison after a dramatic operation involving a van ramming through a gate, ladders used to get above barbed wire and gunfire from automatic weapons.
Milan Poparic is the third 'Pink Panther' to escape from a Swiss prison since May.
BBC notes that the Carlton Hotel is where Alfred Hitchcock filmed To Catch A Thief — his 1955 film about a jewel thief operating in the French Riviera.