French security chiefs are meeting in Paris as Nice's seaside boulevard reopens to traffic Saturday following a dramatic truck attack which killed 84 people and wounded more than 200 others at a fireworks display.

Defense and intelligence leaders are gathering at the Elysee Palace, the official residence of the French president, for talks about the atrocity, the third mass casualty attack against France in 18 months.

Meanwhile the site of the massacre, Nice's famous Promenade des Anglais, was slowly coming back to life Saturday morning. A maskeshift memorial of bouquets, candles and messages had been set up near one end of the expansive avenue.

France is observing three days of national mourning in homage to the victims.