An exhibition in France's Riviera city of Cannes was stormed by an armed robber who took jewelry and gems worth about $136 million on Sunday. (An earlier estimate given by police was $53 million.)

The theft took place at the Carlton intercontinental hotel, an upscale resort that was the backdrop for Hitchcock's film "To Catch a Thief," starring Grace Kelly and Cary Grant.

Disguised by a hat and scarf, the robber threatened to shoot vendors, and then took off by foot with a full briefcase down the city's busy promenade.

Unarmed security guards were on site. The event was held by Leviev diamond house, owned by Israeli billionaire Lev Leviev.

Two other major jewelry heists happened earlier this year during events at the Cannes Film Festival.

In February, eight heavily armed thieves busted though a gate at the Brussels airport and made off with $50 million in diamonds that were in the hold of a Zurich-bound aircraft. Subsequent arrests of 30 people have been made.