NICE, France » Almost instantly, those in its murderous path could tell that the speeding white truck was all wrong so late at night on Nice’s beachfront boulevard whose bright lights glittered along the bay like a string of stars.

The Promenade des Anglais was meant to be closed to traffic, cordoned off with metal barriers and plastic tape, so families and tourists could stroll worry-free beside the azure waters of the Mediterranean and marvel at the Bastille Day fireworks.

The truck sped straight for them, slowing at times, accelerating at others, leaving death, screams and horrific injuries in its wake.

“I realized right away it was a terrorist attack when I saw the truck crushing people,” said Antonio Arribas, who was with his cousin, Diego.

The rented 19-ton (21 U.S.-ton) truck zigzagged for 1¼ miles through holiday crowds like a snow plow, leaving a gruesome trail of crushed and mangled bodies. The 84 dead included French and foreigners, children and adults.

Just when Egyptian tourist Nader El Shafei looked like he might fall next under its large wheels, the truck stopped. The attacker, a 31-year-old Tunisian who lived in Nice and drove for living, was killed by police gunfire.

Moments earlier, as the fireworks show was ending, El Shafei said he’d looked at the large crowds and thought to himself: “If someone crazy want(s) to do something, this is the right place and the right time, among all those innocent people.”

He had traveled to Nice expecting to see “paradise.”

“But I saw something else,” he said.

He caught the scene on video — the crackle of gunshots, officers warily approaching the cab with its windshield pockmarked with holes. El Shafei said he saw the driver, later identified by authorities as Mohamed Bouhlel, fire back through a window.

France’s third attack with mass casualties in 18 months was even more indiscriminate than the others. The dead in Nice included at least 10 children and adolescents. They had come to marvel at the fireworks, “to feel joy, to share in happiness and be dazzled,” said President Francois Hollande.

“And they were struck, struck to death, to satisfy the cruelty of an individual and perhaps of a group,” he said after visiting a hospital that treated victims.

French officials called it an undeniable act of terror, but no group claimed responsibility and it was unclear if the driver had any ties to extremists.

Paris prosecutor Francois Molins said the refrigerated truck was rented in the outskirts of Nice on July 11. It was due back July 13 but instead was parked east of the city.

Bouhlel rode a bike to the truck, Molins said.

About 25 minutes before the fireworks show, he clambered aboard and drove toward the city — and the crowded promenade near Nice’s glittering hotels.

The truck’s murderous journey lasted 15 city blocks.

Video showed the truck moving slowly at one point — so slowly that a man in a white shirt was able, at a run, to catch up with it. There were two sharp sounds as he caught up with it. It was unclear whether the sounds were him banging on its closed back doors to get it to stop, or gunfire.

A speeding motorcycle rider also pulled even with the driver’s cab, swerving with a screech of tires around a pedestrian. The motorcyclist ditched his bike and also ran alongside and even managed to grab the truck to try to get it to stop.

Then the truck dramatically picked up speed as people fled in terror.

“I thought it could either be a drunk driver or a terror attack,” said German tourist Richard Gutjahr, who filmed it from a hotel balcony.

People were hit head on. “A lot of them had been dragged under the lorry and were not recognizable,” English tourist Simon Coates, who was cycling back to his hotel when the truck approached, told the BBC. “I saw some dreadful things. It was like a chamber of horrors. Every person seemed to have died in an increasingly grotesque way.”

Molins said Bouhlel shot at three police officers outside the palatial Negresco Hotel. They fired back and pursued the truck as it continued on for another 300 meters (yards) to the Palais de la Mediterranee Hotel. More shots were fired there.

Bouhlel was found dead in the passenger seat.

El Shafei, the 42-year-old Egyptian, said the truck ran over a girl before it stopped right in front of him.

While someone else pulled the motionless girl out from under the truck, El Shafei said he started to yell at the driver.

He’d seen the truck swerve and the driver wrestle with the wheel before it stopped, he said, making him think this was an accident — a loss of control of the vehicle — until the shots rang out.

“I kept waving to him, ‘Stop, stop! There are people under your truck,’” El Shafei said.

Police urged people to run, he added. He thought, “The truck has a bomb or something or maybe he is a suicide guy.”

Panic gripped the promenade.

Cyril Croisy jumped off a wall to the beach, breaking his arm. He hid there until he felt it was safe to emerge. The Parisian had seen the truck’s trajectory and knew immediately that this was an attack because it careened straight at a stand selling candy to children.

“We heard lots of people screaming, and we saw the truck continuing very, very fast,” he said.

Croisy saw an injured woman and said he crouched to help her. His eyes filled with tears at the still-raw memory.

“I was there when her heart stopped,” he said.

He also heard a ringing phone that apparently belonged to a man who had been mowed down.

Croisy answered it. It was the man’s female companion, a short distance away, looking for him.