A knifeman has killed one person and wounded four in a suspected terror attack in central Paris, French officials have said.
The attacker was then shot dead by police in the Opéra district. Witnesses said they heard him shout "Allah Akbar".
So-called Islamic State (IS) later said one of its "soldiers" had carried out the attack on Saturday evening.
Judicial sources told French media the attacker was a man born in 1997 in the southern Russian republic of Chechnya.
The sources said his parents had been held for questioning.
Interior Minister Gérard Collomb said the victim of the attack was a 29-year-old man, but gave no further details.
French President Emmanuel Macron tweeted: "France has once again paid in blood, but will not give an inch to the enemies of freedom."
The attacker began stabbing passers-by at about 9pm local time on the Rue Monsigny.
The man tried to enter several bars and restaurants but was blocked by people inside.
Police first tried to stop the assailant with a stun-gun before shooting him dead, nine minutes after he began the attack.