Prime Minister Justin Trudeau, U.S. President Barack Obama and other world leaders offered solidarity with France on Thursday after an attack described as terrorism by French President Francois Hollande killed up to 80 people.
"I was heartbroken to learn of the many dozens of innocent victims who were killed or injured as a result of today's terrorist attack that targeted Bastille Day celebrations in Nice, France," Trudeau said in a statement released late Thursday.
"On behalf of all Canadians, I extend my deepest condolences to the families and friends of those who were killed. We also wish a speedy recovery to the many more that were injured.
"Canada and France are the closest of friends, and we stand by the French people as they face this terrible ordeal. We have offered all possible assistance to the French Government.
"Senseless acts like this one are not isolated events, and we will continue to work with our Allies and partners to fight terrorism in all of its forms. We will bring those who are responsible to justice, whether they be the perpetrators, or those involved in funding or organizing such attacks.
"Our thoughts and prayers are with the people of France at this very difficult time. We mourn the loss of so many innocent victims."
Foreign Affairs Minister Stephane Dion added in a separate statement: ""We condemn this horrific terrorist attack, and we offer our deepest condolences to the families and friends of those killed and a speedy recovery to those injured. Canadians are deeply saddened by this tragedy and we stand in solidarity with the people of France on their national day."
At a formal reception in the Montreal Museum of Fine Arts, where the French consul-general, Catherine Feuillet, and Mayor Denis Coderre entertained members of the city's French community, Coderre ordered flags at City Hall to be flown at half-mast and quickly released a statement in which he expressed shock over the scope of the deadly attack.
"In this difficult moment, Montrealers stand in solidarity with the French people and the people of Nice," he said. "Liberté, egalité, fraternité. These values have never been as relevant."
European Council president Donald Tusk said it was a "tragic paradox" that the victims of the attack in Nice were celebrating "liberty, equality and fraternity" — France's motto — on the country's national day, Bastille Day.
"We will stand united with the families of victims, the French people and the government in the fight against violence and hatred," Tusk said at a meeting of Asian and European leaders in the Mongolian capital of Ulaanbaatar. In Washington, Obama condemned "what appears to be a horrific terrorist attack."
Donald Trump, the presumptive Republican nominee for president in this November's election, called off plans to announce his vice-presidential choice because of the bloodshed.
Trump had planned to hold his first event with his yet-to-be-named running mate Friday morning in New York. He announced the change of plans Thursday evening on Twitter.
The stunning announcement raised questions about the status of Trump's selection process. Indiana Gov. Mike Pence had emerged as a late favourite for the job, though Trump said he had not finalized the pick and advisers cautioned he could change his mind.
"I haven't made my final, final decision," Trump said on Fox News Channel. He said that while his running mate selection would "absolutely not" be changed by the France attack, he did not feel it was appropriate to hold a news conference in its aftermath.
Hillary Clinton, also appearing on Fox, said the U.S. needs to "stand strongly" with France and said she would intensify efforts to put together a more effective coalition against terrorism.
We will not be intimidated," she added.
The Democratic presidential candidate says the U.S. and France will never let terrorists undermine democratic values. She says the "cowardly attack only strengthens our commitment to our alliance and to defeating terrorism around the world."
Noting that the attack occurred on Bastille Day, Obama praised "the extraordinary resilience and democratic values that have made France an inspiration to the entire world."
Obama is offering French officials "any assistance that they may need to investigate this attack and bring those responsible to justice."
Elsewhere, there was this reaction
Premier Li Keqiang said "we strongly condemn terrorism of all forms. We express our condolences to the victims and we will fight all kinds of terrorism."
German Chancellor Angela Merkel said Germany would stand by France's side in the "fight against terrorism".
"All of us who have come together at the ASEM summit are united in our feeling of disbelief at the attack of mass murder in Nice," Merkel said on the sidelines of the major summit between Asian and European leaders in Mongolia.
"Germany stands in the fight against terrorism at France's side, united with many, many others. I am convinced that, despite all the difficulties, we shall win this fight."
Prime Minister Narendra Modi condemned what he called a mindless attack.
"I am appalled by the horrific attack in Nice. I strongly condemn such mindless acts of violence. My thoughts are with the families of deceased.
I hope the injured recover soon. India shares the pain and stands firmly with our French sisters and brothers in this hour of immense sadness," Modi said.
Foreign Minister Julie Bishop said three Australians suffered minor injuries while fleeing the scene.
"It has shocked France, it has rocked it to its core," Bishop told reporters in the Western Australia capital of Perth. "This should have been a time of great national pride and celebration."
Bishop condemned the violence, saying it was a reminder that "no country is immune from terrorist attacks."
"We support our friends and partners in France and we join with others around the world in hoping that this will be the end of this type of horrific incident that is targeted at unarmed civilians," she said.
Foreign Minister Didier Reynders expressed dismay that France was once again the target of an apparent terrorist attack.
"We condemn such an attack, maybe a terrorist attack, but such an attack in France again," he said.
Foreign Minister Jose Manuel Garcia-Margallo said he called his counterparts in France to express his condolences.
"We are very sorry and very much with the French people and the French government," he said in at a meeting of Asian and European leaders in the Mongolian capital of Ulaanbaatar.
Prime Minister Taavi Roivs condemned "a terrible attack on innocent people celebrating their national day. Today, we all stand together with the French people."
With files from Laurent Bastien