Police officers and rescue workers stand near a van that struck a crowd that was leaving a fireworks display in Nice, France.Valery Hache/AFP/Getty Images
A truck driver plowed into a crowd watching Bastille Day fireworks on a landmark street in the city of Nice, France, killing scores of people out to enjoy the national holiday.
The mayor of Nice, Christian Estrosi, tweeted that a truck driver killed "dozens."
"Stay for the moment in your home," he added. "More info to come."
The Nice prosecutor's office later told local TV the death toll was estimated to be around 60. That was updated to 73 dead and more than 100 injured at about 7 p.m. EST.
There were reports on the ground of gunfire. The driver -- who was operating a large, cargo-style truck with explosives and weapons inside -- reportedly fired on the crowd, and police then opened fire to stop to the driver. Witnesses reported the driver deliberately accelerating into the crowd, making it about a mile driving up to 30 mph.
Officials confirmed the driver was "neutralized." French officials were also referring to the incident as an attack.
An Agence France-Presse reporter on Promenade des Anglais witnessed a white truck driving into the crowd at a high rate of speed near Hotel Negresco as people were leaving after the fireworks show.
Terror groups have emphasized that jihadists don't need to use guns to create carnage, but use what's at hand to commit attacks. Al-Qaeda in the Arabian Peninsula's Inspire magazine has included cars among the attack means detailed in their English-language instructions.
An English-speaking jihadist in a June ISIS video out of Afghanistan titled "You Won't Dream of Being Secure" directed Muslims in the West to "try your level-best to destroy kuffar [disbelievers]."
"By any means, slaughter them -- hit them by your car, give them poison, stab them with a knife, punch them, or at least spit on them," the terrorist advises.
ISIS-affiliated accounts quickly began tweeting about the attack.
"Death trucks waiting for you," said one. "Way clever attack," admired another. Some tweeted Nice images with Quranic verses. "Allahu Akbar Allahu Akbar Allahu Akbar Allahu rip them to pieces," tweeted another.
One suggested that the attack was revenge for Abu Omar al-Shishani, a Chechen ISIS commander whose death during battle ISIS confirmed Wednesday.
A female ISIS group issued a lengthy statement Wednesday declaring that the Chechen's death would only inspire more Muslims to take up arms -- but the threats specifically named America. "Do not rejoice too much and stay tuned for what is to come -- you will have plenty days of horror," the statement said.
Some ISIS-supporting accounts spread the story that gunmen had taken hostages at a hotel in Nice. France's Interior Ministry said there was no hostage situation.
The Euro Cup was hosted in France with many terror fears -- as it overlapped with Ramadan -- but concluded a week ago with the only violence being fights between fans.
"The president has been apprised of the situation in Nice, France, and his national security team will update him, as appropriate," said National Security Council spokesman Ned Price in a statement released by the White House.
Mayor Estrosi issued another tweet: "This is the worst tragedy in the history of Nice with more than 70 victims already."
UPDATE 8:30 p.m.: President Obama issued a statement condemning "in the strongest terms what appears to be a horrific terrorist attack in Nice, France, which killed and wounded dozens of innocent civilians."
"Our thoughts and prayers are with the families and other loved ones of those killed, and we wish a full recovery for the many wounded. I have directed my team to be in touch with French officials, and we have offered any assistance that they may need to investigate this attack and bring those responsible to justice. We stand in solidarity and partnership with France, our oldest ally, as they respond to and recover from this attack," Obama said.
"On this Bastille Day, we are reminded of the extraordinary resilience and democratic values that have made France an inspiration to the entire world, and we know that the character of the French Republic will endure long after this devastating and tragic loss of life."
The U.S. Embassy in Paris issued an emergency message stating that they were "working with local authorities to determine if any U.S. citizens were injured in the event."
"We urge U.S. citizens in Nice to contact family members and loved ones to notify them that you are safe, avoid the area, to monitor local press for updates, and to exercise caution if you are in the vicinity."
UPDATE 9:50 p.m.: French President Francois Hollande said the death toll is at 77, including some children. He also said 20 of the wounded were in critical condition. He confirmed the driver was shot dead.
The state of emergency that was supposed to end July 26 will be extended by three months.
"Nothing will get us to give in to our will to fight terrorism," Hollande said.
Separately, French officials said they were trying to determine if an ID found in the truck belonged to the attacker. It was that of a 31-year-old French-Tunisian man who lived in Nice.
UPDATE 10:35 p.m. EST: French Interior Minister Bernard Cazeneuve says 80 people are dead and 18 in intensive care.