One person has died and four others injured in a knife attack in Paris.
Police have shot and killed the attacker and launched a terror investigation.
It happened just before 9.00pm last night near where Paris's Opera and landmark shops are located.
The attacker shouted "Allahu Akbar" - God is great in Arabic - according to witnesses, the Paris prosecutor Francois Molins said.
The IS news agency Amaq claimed the suspect was one of its "soldiers" who carried out the attack in response to the terror group's calls for supporters to target members of the US-led military coalition fighting the extremists in Iraq and Syria.
French President Emmanuel Macron said France has "once again paid the price of blood".
He tweeted: "All my thoughts go to the victims and the wounded of the knife attack perpetrated tonight in Paris, as well as to their relatives.
"I salute on behalf of all the French the courage of the policemen who have neutralised the terrorist.
"France once again paid the price of blood but did not give an inch to the enemies of freedom."
La France paye une nouvelle fois le prix du sang mais ne cède pas un pouce aux ennemis de la liberté (2/2).
— Emmanuel Macron (@EmmanuelMacron) May 12, 2018
A witness who was sitting in a restaurant with his girlfriend told Le Parisien: "Just before 9.00pm, we saw people rushing inside the restaurant screaming that a man was outside with a bloody knife.
"People were throwing themselves on the floor in panic.
"Five minutes later there was a second scare and customers blocked the door of the restaurant for fear the attacker had slipped inside.
"Then it calmed down. Outside, even the police seemed a bit lost at first."
