Men, women and children mowed down by terrorist in truck as they celebrated France's Bastille Day on the streets

Nice terror attack: live updates

Men, women and children were out on the streets of Nice in their thousands celebrating Bastille Day as a fireworks display lit up the sky.

Moments later they were running for their lives as a lorry suddenly sped into view, targeting the crowds that lined the promenade for some 200 meters.

As they fled, some were confused as to whether the explosions they heard were the sounds of additional fireworks amplified by their fear, or if a gunfight was underway.

"Everyone was calling run, run, run there's an attack run, run, run. We heard some shots. We thought they were fireworks because it's the 14th of July," one witness told France's BFM TV.

"There was great panic. We were running too because we didn't want to stick around and we went into a hotel to get to safety. "

Sophie Sandilands of Australia told 7 News Sydney that she had just wandered away from the crowd to listen to live music when the attack took place.

"All of a sudden there was just thousands of people running towards us," she said. "The footage we're seeing on TV doesn't truly even accurately describe the sheer mass of people- strollers being knocked over, people being pushed out of the way... we didn't have any choice but to run or be trampled."

An American pilot said he was just feet away as the truck sped past him, and watched as the driver accelerated into the crowd.

As he fled he said he thought he heard gunshots ring out, but he did not look back until he had escaped the area.

Wassim Bouhlel, a Nice native, told the Associated Press that he saw the truck drive into the crowd, and then witnessed the man emerge with a gun and start shooting.

"There was carnage on the road," Mr Bouhlel said. "Bodies everywhere."

A man identified as Manon told Nice Matin newspaper: “The driver had made up his mind, he was going to crash. The van drove onto the pavement. It passed two metres away from us. I saw people lying down  I saw a small child on the ground."

Mobile phone footage spread online showing hundreds of people fleeing the area, with others gathering on balconies to try and determine what was taking place.

Word quickly spread to those in neighbouring streets, flooding the city with panic, confusion and fear.

Anti-terrorism police rushed to the scene, which was already under heightened security because of the occasion and the crowds.

Joel Fenster, a 23-year-old law student from north London who is in Nice for a language course, told The Telegraph how he and friend ran for cover after hearing gunshots.

“We went to watch the fireworks on the beach and then after we knew there was meant to be a concert so we were walking round to the promenade. It was a perfectly normal night,” he said, speaking from his apartment in Nice.

“Suddenly everyone started running in the opposite direction to us, and ducking down. It seemed like there was someone coming - there was a strong sense that we needed to get away. So we started running away from the beach, inland towards the old town.  We heard the gunshots - initially one, then later two more."

Mr Fenster, a Cambridge University graduate, was in Nice for a one month French language course before starting a job at a law firm in London.

He said: “We ran down a road, everyone was ducking down and going into doorways. We ran into an alleyway and crouched down for about an hour. The whole time it was terrifying but didn’t quite feel real.

“We ran into a restaurant that was open, people were rushing into it from the street. At that point we thought there was a shooter running around. The police came and told the owner to turn the lights off and put the shutters down. Everyone got down on the floor, crouching below tables. There were quite a few young children, they were terrified.”

British holidaymaker Esther Serwah, 59, was staying in a hotel a short walk from the scene.

She said she had been on her way to the Promenade des Anglais for dinner with her daughters when people started screaming at her.

Mrs Serwah, from Surrey, said: "I was just walking to the Promenade and then I saw everybody running and I just didn't know what was going on. People were screaming at me in French but I didn't understand.

"Some people were lying on the streets dead and people were running over the bodies. Everybody was saying it's a terrorist attack. It's just horrible, horrible, horrible. I'm in shock. I'm still shaking."

“We were at the Neptune beach and a firework display had just finished," another witness said. "That is when we saw a white lorry. It was going quickly at 60-70 kilometres an hour.”

British visitor Lucy Nesbitt-Comaskey told Sky News: "It sounded like an attack in Beirut, I know that sounds crazy to say, and I said to my friend: 'It doesn't sound like fireworks it sounds like Beirut when it's under attack! 

"And all of a sudden people were screaming in the street and they were running, all to the restaurants. All the restaurants were open and people were coming and we were just sitting there and everybody came into our restaurant, and the owners of the restaurant were closing the doors saying: 'Please don't go anywhere, get in, get in everybody.'

"Everybody was screaming, there was a lady, she collapsed on the floor, she fainted, and were were in shock."

She added: "We were literally one block away. It was shocking, it was devastating, I can't believe I've come over here for a few days and I've got mixed up in something so tragic." 

Journalist Isabel Hardman said: "I had been watching fireworks on le Promenade des Anglais, which is down by the sea in Nice, to celebrate Bastille Day, and I was walking back and suddenly there were shouts and people started running away from the main square and there was screaming and suddenly lots of sirens started up and there were police cars and ambulances whizzing past.

"I kept stopping people and saying 'qu'est-ce qui se passe' and they said 'je ne sais pas'. No one knew what they were running from.

"So we just kept walking and went back to the flat where I'm staying. I bumped into a family who had a young child with them who had been told by the police to go inside, so they have come inside too."

Zeynep Akar, another witness, spoke from near the scene of the attack after it had concluded.

She told CNN  the crowd was lined up for 200 meters along the road, and that the driver went straight through from one end to the other.

She said the wounded had been rushed from the scene, but that the dead remained all along the street.

"The truck is still there too," she said.