Washington – US President Barack Obama condemned as an "attack on all of humanity" on Friday's wave of bombings and shootings in Paris that prompted increased security in New York and Washington.
"Those who think that they can terrorise the people of France or the values that they stand for are wrong," Obama said in a hastily convened appearance before reporters at the White House, as the death toll surged past 120 and US sports venues ramped up security.
"We are reminded in this time of tragedy that the bonds of liberte, egalite, fraternite, are not just the values French people share, but we share," he said, citing France's national motto.
"Those go far beyond any act of terrorism or the hateful vision of those who perpetrated the crimes this evening."
The Department of Homeland Security reported there was "no specific or credible threat to the United States" in the wake of the attacks.
But authorities in New York and in the capital Washington - both hit in the 9/11 terror attacks in 2001 - were placed on a heightened state of alert and counterterrorism police reinforcements deployed to crowded public places as a precautionary measure.
Units were also deployed to French-owned sites, such as the French mission to the United Nations and the French Consulate in New York.
French colours light up New York
The New York Police Department said its intelligence division was "conducting liaison activities to assist the Paris police in any way possible."
One World Trade Center, the tallest building in the Western hemisphere and built on the site of the Twin Towers, destroyed in the 9/11 attacks, lit its giant antenna in red, white and blue in tribute to France.
"Today, and in the days ahead, New York will light One World Trade Center in blue, white and red as we stand in solemn solidarity with the people of France," state Governor Andrew Cuomo said.
Meanwhile, Obama's former secretary of state, Hillary Clinton, offered her "prayers" to the victims and their families.
Also read: Multiple terror attacks in Paris
"All our prayers are with the people of France tonight," Clinton, a 2016 Democratic presidential contender, said.
"We must stand side-by-side every step of the way with France and our allies around the world to wage and win the struggle against terrorism and violent extremism," the former US first lady added.
"Even in this darkest night, Paris remains the City of Light. No terrorist attack will ever dim the spirit of the French people or our common commitment to the democratic values we share."
Obama and President Francois Hollande spoke by phone after the attacks and vowed to reinforce their counter-terrorism cooperation.
"The president reiterated the United States' steadfast, unwavering support for the people of France, our oldest ally and friend, and reaffirmed the offer of any necessary support to the French investigation," a White House statement said late on Friday.
'Bring terrorists to justice'
And in remarks earlier in the evening, Obama pledged to work with France to bring those responsible to justice.
"Whenever these kinds of attacks happen, we've always been able to count on the French people to stand with us. They have been an extraordinary counterterrorism partner," Obama said.
"We stand prepared and ready to provide whatever assistance the government and people of France need to respond.
"It's an attack not just on the people of France. But this is an attack on all of humanity and the universal values we share."
Obama also expressed his resolve in tackling terror.
"We're going to do whatever it takes to work with the French people and with nations around the world to bring these terrorists to justice and to go after any terrorist networks that go after our people."
Vice President Joe Biden echoed that sentiment, saying "such savagery can never threaten who we are. We will respond. We will overcome. We will endure."
Secretary of State John Kerry said the US Embassy in Paris was attempting to make sure Americans in the city were all accounted for.