Cannes ( CNN ) -- The value of jewels stolen from an exhibition in the French resort city of Cannes on Sunday is close to $ 136 million -- more than twice the amount stated in earlier reports -- the Nice prosecutor 's office told CNN Monday . The robbery -- the third such heist around the city since May -- happened Sunday morning at a jewelry exhibition at the Carlton Hotel , according to Philippe Vique , deputy prosecutor for organized crime in the prosecutor 's office . Earlier , a Nice police official told CNN on condition of anonymity that the jewels were worth about $ 53 million . The robber , whose face was covered by a hat and a scarf , had a semiautomatic pistol and threatened to shoot the exhibitors and guests , Vique said . Jewelry thefts reported at Cannes . Security guards were present but unarmed , he said . No one was injured . The gems were supposed to have been on display until the end of August . The robbery follows two major jewel heists this year at events tied to the Cannes Film Festival . During the festival in May , a necklace worth $ 2.6 million was stolen from a hotel party shortly after jewels worth more than $ 1 million were stolen from a safe in a hotel room . Jeweler de Grisogono said the necklace was part of a collection making its debut . The jewels stolen in May were from the Swiss firm Chopard , which was sponsoring the festival . Notable diamond heists . CNN 's Stephanie Halasz , Vladimir Duthiers and Lauren Russell contributed to this report .
A police official said earlier that the jewels were worth about $ 53 million . The jewelry was found in a safe deposit box at an office building on the outskirts of New Delhi and is believed to have been stolen from a jewellery store there last year. Sunday 's heist happened at a jewelry exhibition at the Carlton Hotel .