The truck driver who killed 84 people celebrating Bastille Day in the French Riveria city of Nice was purposefully aiming the vehicle at the crowd and "zigzagging" so that he could hit as many people as possible.
According to media reports, the attacker drove into the crowd for about 2 km before he was overpowered.
Damien Allemand, journalist with the Nice-Matin newspaper who was at the waterside, said the fireworks display had finished and the crowd had got up to leave when they heard a noise and cries.
"A fraction of a second later, an enormous white truck came along at a crazy speed, turning the wheel to mow down the maximum number of people," he said, adding, "I saw bodies flying like bowling pins along its route. Heard noises, cries that I will never forget."
An eyewitness told BFM TV: 'Everyone was calling run, run, run... there is an attack run, run, run. We heard some shots. We thought they were fireworks because it's the 14th of July.'
'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.
Alex Maule, who hid in a casino for over than an hour after the attack, told ITV News: "People were screaming and shouting. There were running all over the place. They were shouting 'there's a lorry, there's a lorry.' It was chaos. They started bringing people inside one by one in various states of injury -- some had head wounds, some were bleeding from their arms or legs.
"They were bringing unconscious children in."
"I walked on to the promenade later and it was littered with dead bodies covered in table cloths," she said.
Harjit Sarang, 42, a surrogacy lawyer from London who was in the city with her husband and two young sons -- aged six and nine -- said on Twitter: 'Running through crowds in Nice with kids and terrified. Never taking kids to a public event again. Finally back to hotel. Hate this! #nice. Can't stop shaking. Hate that my boys had to experience this. Why did I take them. Why did they do this and why the f*** is this happening!'
Wassim Bouhel told the French TV channel iTele that the lorry zigzagged across the road.
He said: "We almost died. It was like hallucinating ... (the lorry) zigzagged - you had no idea where it was going. My wife ... a metre away ... she was dead. The lorry ripped through everything ... poles, trees."
"We have never seen anything like it. Some people were hanging on the door and tried to stop it."
Brit Will Shore told BBC Radio 4: “It was quite chaotic really. There was a lot of people screaming, running around and people were kind of being pushed over, I think, from people just being so frightened about what was going on especially after hearing the gunshots.
“I had to help a couple of people up who were in distress on the floor because everyone was in such a panic.”
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