A gunman at the wheel of a heavy truck plowed into a crowd celebrating Bastille Day in the French city of Nice on Thursday, killing at least 84 people and injuring scores more in what President Francois Hollande called a terrorist act.
The attacker, identified by a police source as a 31-year-old Tunisian-born Frenchman, also opened fire before police shot him dead. He had been known to the police for common crimes but not to the intelligence services, the source said.
Interior Minister Bernard Cazeneuve said 18 of the injured were in a critical condition after the 25-ton truck zigzagged along the seafront Promenade des Anglais as a fireworks display marking the French national day ended just after 10:30 p.m. local time.
The attack, which came eight months and a day after self-styled Islamic State terrorist group's gunmen and suicide bombers struck Paris on a festive Friday evening, seemed so far to be the work of a lone assailant.
Hollande said in a pre-dawn address that he was calling up military and police reservists to relieve forces worn out by a state of emergency begun after the militant group killed 130 people in the French capital in November.
Only hours earlier, Hollande had announced the state of emergency would be lifted by the end of July, but the president said that following the attack, in which several children were killed, it would now be extended by a further three months.
Hollande called the tragedy on the day that France marks the 1789 revolutionary storming of the Bastille prison in Paris as an attack on liberty by fanatics who despised human rights.
France would, nonetheless, continue its air operations against IS in Syria and Iraq.
Officials said hundreds were hurt as the driver wove along the seafront, knocking them down "like skittles". A local government official said weapons and grenades were found inside the unmarked articulated truck.
Police were trying to establish whether the driver might have had any accomplices in a city with a reputation for militant activism.
"A Scene of Horror"
The truck careered into families and friends listening to an orchestra or strolling above the beach toward the grand, century-old Hotel Negresco.
"It's a scene of horror," member of parliament, Eric Ciotti, told France Info radio, saying the truck "mowed down several hundred people".
Jacques, who runs Le Queenie restaurant on the seafront, told the station: "People went down like ninepins."
Major events in France have been guarded by troops and armed police since the IS attacks last year, but it appeared to have taken many minutes to halt the progress of the truck as it tore along pavements and a pedestrian zone.
US President Barack Obama said in a statement: "On behalf of the American people, I condemn in the strongest terms what appears to be a horrific terrorist attack in Nice, France, which killed and wounded dozens of innocent civilians."
The United Nations Security Council said it "condemned in the strongest terms the barbaric and cowardly terrorist attack".
On social media, IS supporters celebrated the high death toll.
- Prior Warnings
Nice-Matin journalist Damien Allemand had been watching the traditional seaside firework display when the truck tore by just as it ended. After taking cover in a cafe, he wrote on his paper's website of what he saw when he came back out on the promenade: "Bodies every five meters, limbs ... Blood. Groans."
"The beach attendants were first on the scene. They brought water for the injured and towels, which they placed on those for whom there was no more hope."
Officials have warned in the past of the risk of militan attacks in the region following the Paris and Brussels attacks.
Reverses for IS in Syria and Iraq have raised fears it might strike again in Europe, possibly again using alienated young men from the continent's Arab immigrant communities whom it has inspired to take up arms against their native countries.
