NICE, France — The toll of an attack on a Bastille Day fireworks celebration in the southern French city of Nice rose on Friday to 84 dead and 202 injured, as the government identified the assailant as a 31-year-old native of Tunisia, extended a national state of emergency and absorbed the shock of a third major terrorist attack in 19 months.
“We will not give in to the terrorist threat,” Prime Minister Manuel Valls said Friday morning after a cabinet meeting led by President François Hollande. But Mr. Valls also offered a grim observation for his countrymen: “The times have changed, and France is going to have to live with terrorism.”
Starting around 10:45 p.m. Thursday, the attacker mowed down scores of victims in Nice with a rented 19-ton refrigerated truck before engaging in a gunfight with three police officers, who pursued him down a storied seaside promenade before finally killing him.
The Paris prosecutor, François Molins, identified the man as Mohamed Lahouaiej Bouhlel, who was born on Jan. 3, 1985, and raised in Msaken, a town in northeastern Tunisia.
The police searched two locations in Nice on Friday, including a home with Mr. Bouhlel’s name outside it, and workers in hazardous-materials suits searched a truck, one much smaller than the one used in the attack. His ex-wife was held for questioning.
No organized group has claimed responsibility for the attack, although online accounts associated with the Islamic State and Al Qaeda have cheered it.
Mr. Bouhlel had a history of petty crime, including theft, going back to 2010, and he received a six-month suspended sentence in March for assaulting a driver during an altercation in January.
“However, he is completely unknown by intelligence services, both at the national and local levels,” Mr. Molins said. “He has never been in any database or been flagged for radicalization.”
Mr. Bouhlel rented the truck on Monday from a company in Saint-Laurent-du-Var, a town about six miles east of Nice, near the city’s airport, and then parked it in the Auriol neighborhood of eastern Nice.
At 9:34 p.m. on Thursday, according to surveillance footage, Mr. Bouhlel arrived by bicycle in Auriol and entered the truck. He then drove it westward, arriving at 10:30 in the Magnan neighborhood, north of the Promenade des Anglais, a famous seaside boulevard.
His deadly rampage began around 15 minutes later, when he drove the truck south and then turned onto the promenade, which was packed with spectators watching the end of the Bastille Day fireworks.
Mr. Bouhlel initially mowed down two people and then continued driving for 1.1 miles eastward, running over people left and right. Outside the Negresco Hotel, Mr. Bouhlel fired at three police officers; they returned fire, and then pursued him for about a thousand feet. They shot and killed him outside a Hyatt hotel and casino.
Mr. Bouhlel was found dead in the passenger seat. In the truck’s cabin, police found an automatic 7.65 mm pistol, a cartridge clip, and several cartridges. They also found a fake automatic pistol; two fake assault rifles, a Kalashnikov and an M-16; a nonfunctioning grenade; and a mobile phone and documents.
The 84 dead included 10 children and teenagers, Mr. Molins said. Among the victims were two German students and their teacher;two Americans; two Tunisians, andone Russian. Of the 202 people wounded, 52 had serious injuries and 25 were in intensive care, Mr. Molins said.
Officials canceled festivities in Nice, a city of 340,000, including a five-day jazz festival and a concert on Friday night by Rihanna.
“There are many children, young children who had come to watch fireworks with their family, to have joy, to share happiness, delight, amazement, and who were struck, struck to death, merely to satisfy the cruelty of an individual — and maybe of a group,” Mr. Hollande said, flanked by Mr. Valls and Health Minister Marisol Touraine, after meeting with victims and medical workers at the Pasteur Hospital in Nice.
Mr. Hollande said the victims were physically and psychologically scarred. “Many told me that they had no recollection of what might have caused their wounds,” he said. “However, they remember the bodies that were torn to shreds right in front of their eyes.”
Despite mounting criticism over France’s efforts to prevent terrorism attacks, Mr. Hollande praised French security forces, saying they had “taken all necessary measures so that this fireworks show might be as protected as possible — as had been the case during the European Championship soccer tournament.”
“Why Nice?” Mr. Hollande asked. “Because it is a city that is known worldwide, one of the most beautiful cities on the planet,” he said. “Why on the 14th of July? Because it is a celebration of freedom. It was, therefore, indeed to affect France that the individual committed this terrorist attack.”
Hours before the carnage in Nice, Mr. Hollande had said that a state of emergency put in place after the Nov. 13 attacks in and around Pariswould end soon. The government will now seek to extend the state of emergency for three months.
As France announced three days of national mourning, starting on Saturday, world leaders — from Pope Francis and President Obama to Chancellor Angela Merkel of Germany and Britain’s new prime minister, Theresa May — expressed sympathy and outrage.
It was a sadly familiar ritual for France, where a total of 147 people were killed in terrorist attacks in and around Paris in January and November of last year, and it raised new questions throughout the world about the ability of extremists to sow terror.
The internet reverberated with calls for prayer for victims of attacks inBrussels; Istanbul; Orlando, Fla.; Baghdad; and other cities struck by mass terrorism attributed to Islamist extremists this year.
“The horror, the horror has, once again, hit France,” Mr. Hollande told the nation early Friday morning before leaving for Nice.
“France has been struck on the day of her national holiday,” he said. “Human rights are denied by fanatics, and France is clearly their target.”
The attacks could add to the political problems facing Mr. Hollande, who is expected to seek a second five-year term next year even though he is deeply unpopular. On Friday, criticisms of the government’s seeming inability to prevent attacks began to emerge.
Alain Juppé, a former prime minister and one of the main candidates in the center-right primary for next year’s presidential election, told RTL radio Friday morning that “if all the means had been taken, this tragedy would not have occurred.”
Mr. Juppé called for better coordination among France’s intelligence agencies, as a parliamentary inquiry recommended this month.
Georges Fenech, a center-right lawmaker who presided over the parliamentary inquiry, said on Twitter early Friday that the attack a “predictable tragedy.”
Two of the main measures Mr. Hollande announced on Friday — extending the state of emergency and maintaining military patrols around the country at a high level — have been deemed of limited use in thwarting attacks, according to the parliamentary inquiry. The group called for the merging of some of France’s multiple intelligence agencies and the creation of a national coordinating body like the National Counterterrorism Center that the United States established after the Sept. 11, 2001, attacks.
“I don’t want to hear about national unity,” Mr. Fenech told the news channel iTélé on Friday. “Today, it is a duty to talk to the French people, to tell them that our country is not equipped against Islamist terrorism.”
“I am saying it very clearly, whatever the political cost,” he said.
Christian Estrosi, the president of the Provence-Alpes-Côte d’Azur region, which includes Nice, expressed outrage, sympathy and frustration in an interview with BFM-TV on Friday morning, pointedly noting the attacks in France last year, as well as the ones in March in Brussels.
“Questions are raised,” he said. “As I try to comfort the families, I also try to contain my anger, I can’t hide to you that I feel a deep anger. How is it possible in our country that after everyone said there was a state of emergency, a state of war, we forget it, after Charlie Hebdo and the Bataclan. After the Bataclan, we forgot, and there was Brussels. After Brussels, we forgot, and there was Nice, so there are questions that need to be answered.”
Mr. Estrosi said that the families needed time to mourn, and that it was “our duty” to support them. But he also asked how it was possible that the attack had apparently been able to breach security, and he said he expected an answer from Bernard Cazeneuve, the interior minister.
“I don’t want to hear the usual ‘we are going to have an investigative commission,’ ” he said.
The Nice attack took place less than a week after the end of the European soccer tournament. France had hosted the tournament, and the entire country had been on high alert.
With tens of thousands of people gathered at stadiums and in designated “fan zones” during the games, the police and private security forces took extraordinary measures to try to secure the sites.
Some criticism also came from social media, where commentators said that a government app, set up to post alerts in case of emergencies, and unveiled before the tournament, had been too slow to send out a notification about the attack.
The use of a large commercial truck as the principal weapon of death also raised new questions about how to prevent such attacks.
Witnesses to the Nice attack described scene of mayhem.
“We were enjoying the celebrations when we suddenly saw people running everywhere and tables being pushed down by the movement of panic,” said Daphné Burandé, 15, who was at a bar near the beach to watch the fireworks.
“No one explained to us what was happening, and I heard some gunshots not very far away,” she said. “I waited at the bar for more information because I thought it was a false alert. But then, people were still running.”
Another witness, Raja el-Kamel, 43, said the attack seemed, at first, as if it might have been the act of a drunken driver.
“There was a white truck that was advancing slowly,” Ms. Kamel said. “Then it started to plow into the crowd, zigzagging and crushing people. I could not believe it.”
She added: “I was looking on my right, and there were bodies on the ground. I was looking on my left, there were also many bodies on the ground. It was a massacre.”
Joëlle Nouvel, 60, a retired diplomat who has been living in Nice for 15 years, said she saw the truck’s driver wielding a gun in his left hand, and shooting through the truck’s window at the police and at the crowd.
“The truck was ramming over everything and everyone and bodies were thrown in the air like bowling pins,” she said in a phone interview, estimating that she heard about 50 shots fired.
“I saw a man with his 13-year-old girl who had been crushed to death and he was cradling her in his arms,” Ms. Nouvel said. “Everyone was screaming. The truck came within 50 centimeters of me. I was wearing a white dress and it was soon stained with others’ blood. It took about two minutes for the truck to travel two kilometers. It was a carnage.”
Ms. Nouvel said she was flabbergasted that a truck was able to gain access to a crowd of tens of thousands of people on Bastille Day.
“I am shocked at the French government’s failure in the face of jihadists,” she said. “We have no security. The government is just not up to it.” She said she feared an anti-Muslim backlash. “I am simply devastated,” she said.