They are Franco-Tunisian Ramzi A, Tunisian Chokri C, Mohamed Oualid G, Albanian Artan H, and his wife Enkeledja Z who holds both French and Albanian nationality.
Authorities had initially pointed to a rapid radicalisation by Lahouaiej Bouhlel, after several members of his family and friends said he showed no sign of being religious.
Molins said photos on his phone showed he had likely staked out the event in 2015, and initial details of the investigation reveal he had been fascinated with jihad for some time.
"It appears... that Mohamed Lahouaiej Bouhlel planned and developed his criminal project for several months before taking action", said Molins.
Surveillance cameras and other photographs link at least two of the men to the truck, Molins said, and one of the men allegedly provided Bouhlel with the firearm he used to shoot at police in the attack. He also fired an automatic pistol at police before they shot and killed him. The prosecutor said a text message from the same man found on a phone seized at Bouhlel's said: "I'm not Charlie; I'm happy".
A day after that text was sent, on January 11, millions of French people rallied in Paris and other French cities under the slogan "Je Suis Charlie" (I am Charlie) in solidarity with the victims at the satirical newspaper.
Hours after the attack, prosecutors said one of the accomplices also filmed the bloody scene on the promenade.
Interior Minister Bernard Cazeneuve's clarification comes after a newspaper accused French authorities of lacking transparency in their handling of the massacre.
In July 2015, he took photos of the crowd at the Bastille Day fireworks display, as well as another crowd watching a concert on the Promenade Des Anglais three days later.
Cazeneuve launched an internal police probe into security measures taken for the Bastille Day celebrations in Nice shortly after Thursday's backtrack.
Speaking from Ireland, French President Francois Hollande said the inquiry was to seek answers about whether security plans were sufficient, but called for calm.
On Wednesday, French MPs voted to allow the authorities to search luggage and vehicles without prior approval from a prosecutor, and to permit police to seize data from computers and mobile phones.
The paper quoted Nice police officer Yves Bergerat, who said the guns and bullets of the local force are not even equipped "to puncture the tyres", let alone shatter the windscreen, of a truck that size. The main roadblock at the start of the promenade was manned by six national police officers, who were "the first to confront the deadly lorry", he said, adding that two police cars of the national police were stationed there.
Since November, the authorities have had emergency powers to carry out searches by day or night and place people under house arrest.