An accomplice told the Nice Bastille Day killer to 'load the truck with 2,000 tonnes of iron, release the brakes and I will watch' months before the terror attack which killed 84 people.

The Bastille Day truck attack had been planned for 'several months' and terrorist Mohamed Lahouaiej Bouhlel had 'support and accomplices' before he went on the deadly rampage, a prosecutor has revealed.

Prosecutor Francois Molins said five suspects currently in custody are facing preliminary terrorism charges for their alleged roles in helping Bouhlel, in a judicial inquiry opened on Thursday.

Molins said information from the terrorist's phone showed searches and photos that indicated he had been studying an attack since 2015.

Four men and a woman are accused of being 'involved in the preparation' of the attack. The five suspects were presented to anti-terrorism judges and charged with a number of crimes, including complicity to murder and possessing weapons tied to a terrorist enterprise.

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French police have found a Kalashnikov rifle and a bag of ammunition in the basement of the man they believed received text messages from the Bastille Day attacker Mohamed Lahouaiej Bouhlel, pictured right

'Investigations have not only confirmed the premeditated nature of the attack, but allowed us to establish that (Bouhlel) had support and accomplices in the preparation and execution of his criminal act,' Molins said.

In one chilling turn of events, Molins said that one of the suspects, a Tunisian named Mohamed Oualid G, had filmed the scene of the crime the day after the carnage, as it crawled with paramedics and journalists.

Analysis of Bouhlel's telephone revealed pictures taken at a Bastille Day fireworks display in Nice in 2015, as well as a concert on the Promenade des Anglais on July 17, 2015, at which he had zoomed in on the crowd.

On May 26 last year, he took a photo of an article about the drug Captagon which Molins said was 'used by some jihadists responsible for attacks'.

'It appears... that Mohamed Lahouaiej Bouhlel planned and developed his criminal project for several months before taking action,' said Molins.

On April 4, another Tunisian, Chokri C, 37, had sent Bouhlel a Facebook message reading: 'Load the truck with 2,000 tonnes of iron... release the brakes my friend and I will watch'.

More than 400 investigators have been poring over evidence since the July 14 attack in which Bouhlel rammed a truck into crowds on the Nice promenade, leaving 84 dead and over 300 injured.

FRENCH MINISTER ADMITS NO NATIONAL POLICE WERE AT ENTRANCE TO NICE WALKWAY France's interior minister has acknowledged there was no national police presence at the entrance to a pedestrianised walkway in Nice during the Bastille Day truck attack that killed 84 people. In what represents a backtracking from his previous claim that there was, Bernard Cazeneuve says local police, who are more lightly armed, were guarding the entrance where Mohamed Lahouaiej Bouhlel drove his truck. Cazeneuve defended himself against charges in French newspaper Liberation he lied publicly about there being a national police presence at the entry point - with their cars blocking the road. In a statement, Cazeneuve accused the paper of conspiracy theories and maintains that several 'heroic' national police - who shot dead the attacker - were stationed further down the promenade. Advertisement

The news comes after French police found a Kalashnikov rifle and a bag of ammunition in the basement of a man they believe received text messages from the Bastille Day attacker just minutes before the massacre.

The raid was reportedly carried out as part of the investigation into the 22-year-old who allegedly discussed weapons with Bouhlel on the night he drove a truck into a crowded promenade in Nice.

Investigators said data found on Bouhel's mobile phone indicate he was also studying several locations where crowds gathered.

One photo shows a fireworks display on August 15, another a race on January 10 along the Promenade des Anglais where the attack took place, while a third shows the opening times of a fan zone during Euro 2016.

However, Jean-Pascal Padovani, the lawyer for the 22-year-old suspect, has denied 'any implication in a terrorist act' by his client.

Among the other suspects appearing in court are another three men and one woman aged between 22 and 40.

They include a 40-year-old whom Bouhlel had known for a long time and a 38-year-old Albanian, detained along with his girlfriend and suspected of providing the attacker with an automatic pistol.

Like Bouhlel, none of those arrested were known to French intelligence prior to the attack.

It comes as the French government is scrambling to reassure a jittery population after the country's third major attack in 18 months.

France's National Assembly and Senate are also set to pass a bill extending the state of emergency - which gives police extra powers to carry out searches and place people under house arrest - for six months.

The massacre on the Promenade des Anglais left 84 people dead after Bouhlel drove a truck into the crowds

The truck that Bouhlel used to mow down the victims who had been watching Bastille Day fireworks in Nice

It is the fourth time the security measures have been extended since Islamic State jihadists struck Paris in November, killing 130 people at restaurants, a concert hall and the national stadium.

On Wednesday, MPs also voted to allow authorities to search luggage and vehicles without prior approval from a prosecutor and to allow the police to seize data from computers and mobile phones.

The legislation also makes it easier for authorities to shut down places of worship where calls for violence and hate are made.

ISIS posted a video apparently shot in Iraq, where they holds swathes of territory, showing two French-speaking jihadists threatening more attacks against France

ISIS has said the Tunisian driver was one of its 'soldiers' but investigators say that while he showed a recent interest in jihadist activity, there was no evidence he acted on behalf of the extremist group.

The group posted a video apparently shot in Iraq, where ISIS holds swathes of territory, showing two French-speaking jihadists threatening more attacks against France.