In a late-night address to the nation, French President Francois Hollande linked the deadly "terrorist attack" in Nice to the conflict in Iraq and Syria -- and said France will intensify its military operations there in the aftermath of today's tragedy.
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No group has claimed responsibility for the attack, in which a large truck plowed into a crowd in Nice, France, killing at last 80 people late Thursday. But Hollande said that "the terrorist nature" of the attack "cannot be denied."
"Nothing will lead us to give in, to give up our fight against terrorism. We will continue to reinforce our actions in Syria and Iraq," Hollande said, according to a translation of his remarks by France 24. "We will continue to strike those who are attacking us on our own soil."
French officials said investigators are working to identify the driver of the truck, who was killed in the attack, and determine if anyone else was involved.
Prior to tonight's tragedy, France had been targeted in two major terrorist attacks within the last year and a half. In January 2015 extremists linked to both al Qaeda and ISIS killed 12 people in an assault on the French satirical magazine Charlie Hebdo in Paris. In November the same year, an ISIS cell killed 130 people in coordinated attacks also in Paris.
"It is France as a whole that is threatened by Islamist terrorism," Holland said today.
In the past, both ISIS and al Qaeda have encouraged their followers to kill Westerners by using vehicles as weapons. After the Nice attack, online ISIS supporters expressed jubilation at the carnage, widely sharing the sentiment, "They brought this on themselves."
In the wake of the November 2015 attacks in Paris, an ISIS fighter appeared in a video online threatening France again.
"By Allah, the horror and attacks in France will not stop as long as your planes continue to be in our skies," he said.
France is a "key player" in the U.S.-led coalition in Iraq and Syria fighting against ISIS, according to the U.S. Department of Defense.
The European nation has provided 3,500 troops to train Iraqi forces, and French fighter jets have gone on nearly 3,000 missions to strike ISIS targets in what the defense ministry called an "intensive air campaign."
The ministry reported that a joint operation conducted just last week with Belgian fighter jets "served to destroy a huge site used for assembling and storing improvised bombs" near Mosul, Iraq.