Republican presidential candidate Donald Trump says in the aftermath of a deadly truck attack in France that if he’s elected president he would ask Congress for a declaration of war on the Islamic State.

In an interview with Fox News Channel’s “The O’Reilly Factor,” Trump says, “This is war.” He spoke after a truck carrying weapons and hand grenades drove onto a sidewalk in Nice, France, and plowed through people celebrating Bastille Day, killing at least 77 people.

Trump says to fight the Islamic State, which he calls a “cancer,” NATO should be used “for a purpose.”

It was not immediately clear Thursday night who was behind the attack.

In a separate interview on Fox, Democratic candidate Hillary Clinton says the U.S. needs to “stand strongly” with France and strengthen our alliances, including with NATO, to ferret out terrorism and prevent future attacks. Clinton says she would intensify efforts to put together a more effective coalition against terrorism.

(AP)