A boy places a white rose on the road in front of the Negresco hotel before a minute of silence on the third day of national mourning to pay tribute to victims of the truck attack along the Promenade des Anglais on Bastille Day that killed scores and injured as many in Nice, France, July 18, 2016. REUTERS/Eric Gaillard - RTSIHE0

A view shows the crowd gathering near a makeshift memorial on the Promenade des Anglais during a minute of silence on the third day of national mourning to pay tribute to victims of the truck attack along the Promenade des Anglais on Bastille Day that killed scores and injured as many in Nice, France, July 18, 2016. REUTERS/Eric Gaillard - RTSIHTU

People gather in front of the Monument du Centenaire during a minute of silence on the third day of national mourning to pay tribute to victims of the truck attack along the Promenade des Anglais on Bastille Day that killed scores and injured as many in Nice, France, July 18, 2016. REUTERS/Pascal Rossignol - RTSIIE5

A woman's hand with a rose before a minute of silence on the third day of national mourning to pay tribute to victims of the truck attack along the Promenade des Anglais on Bastille Day that killed scores and injured as many in Nice, France, July 18, 2016. REUTERS/Jean-Pierre Amet - RTSIIHO

A slogan which reads "Faithfull City of Nice in memoriam" is seen on the pavement before a minute of silence on the third day of national mourning to pay tribute to victims of the truck attack along the Promenade des Anglais on Bastille Day that killed scores and injured as many in Nice, France, July 18, 2016. REUTERS/Jean-Pierre Amet - RTSIIJW

A soldier from the French Foreign Legion patrols on the Promenade des Anglais on the third day of national mourning to pay tribute to victims of the truck attack on Bastille Day that killed scores and injured as many in Nice, France, July 18, 2016. REUTERS/Eric Gaillard - RTSIJ72

People gather near a heart shape makeshift memorial with a U.S. flag placed on the road in tribute to victims before a minute of silence on the third day of national mourning to pay tribute to victims of the truck attack along the Promenade des Anglais on Bastille Day that killed scores and injured as many in Nice, France, July 18, 2016. REUTERS/Eric Gaillard - RTSIHHT

A woman and a child stand near a makeshift memorial placed on the road during a minute of silence on the third day of national mourning to pay tribute to victims of the truck attack along the Promenade des Anglais on Bastille Day that killed scores and injured as many in Nice, France, July 18, 2016. REUTERS/Eric Gaillard - RTSIHVY

Soldiers from the French Foreign Legion patrol on the Promenade des Anglais on the third day of national mourning to pay tribute to victims of the truck attack on Bastille Day that killed scores and injured as many in Nice, France, July 18, 2016. REUTERS/Eric Gaillard - RTSIJ6Q

A general view shows the Promenade des Anglais after a minute of silence on the third day of national mourning to pay tribute to victims of the truck attack along the Promenade des Anglais on Bastille Day that killed scores and injured as many in Nice, France, July 18, 2016. REUTERS/Eric Gaillard - RTSIHZC

A French flag flies among the crowd as people applaud in front of the Monument du Centenaire during a minute of silence on the third day of national mourning to pay tribute to victims of the truck attack along the Promenade des Anglais on Bastille Day that killed scores and injured as many in Nice, France, July 18, 2016. REUTERS/Pascal Rossignol TPX IMAGES OF THE DAY - RTSIJ6X