Prime Minister Manuel Valls joined thousands packing the Nice seafront for a minute of silence in homage to the victims.
French police are questioning seven people who had connections to the man behind the truck attack that killed at least 84 people as they celebrated Bastille Day in Nice.
Several people arrived under police escort in Paris on Monday for questioning at the headquarters of France’s counter-terrorism department in the western edge of the French capital.
Investigators are also analysing a text message to the person who allegedly gave him a gun.
They are are also looking at the level of preparation undertaken by Mohamed Lahouaiej-Bouhlel after it emerged that he was seen by CCTV cameras on Nice’s seafront Promenade des Anglais twice in the two days before the attack.
The authorities have yet to produce evidence that Tunisian born Bouhlel who was shot dead by police, had any links to ISIL which has claimed the attack. However France’s prime minister claims there is no doubt on the assailant’s motives.
Prayers and mourning
On Sunday members of the French city’s Muslim community came together to pray for the victims. Among the worshippers were several who were on the Promenade des Anglais when Bouhlel drove his truck at speed into the crowd.
France has been observing three days of mourning which continued with a minutes silence held in Nice and across the country at midday.
French Prime Minister Manuel Valls joined thousands packing the seafront, scene of the Bastille day carnage, for the silent homage to the victims.
Anger and falling confidence
But for some the grief is mixed with anger. There were jeers as Valls and local politicians departed and some in the crowd held placards calling for President Francois Hollande to resign.
The French government has been accused of failing to provide enough police on the day – an accusation the prime minister has denied.
Faith in the government is falling. An opinion poll published in Le Figaro newspaper on Monday. showed only 33 percent of respondents were confident in the current leadership’s ability to meet the challenge.
That was sharply lower than the ratings of 50 percent upwards in the wake of two major attacks last year.