Transcript for Knife-wielding man kills 1 person, attacks others in Paris

But we begin with that deadly attack in Paris. A man, armed with a knife, triggering fear and chaos on the streets in a famous neighborhood. Killing at least one person, injuring several others before being shot and killed by police. It happened on a busy street in the popular opera district. People rushing to hide inside restaurants and cafes. Witnesses say what they heard made them believe it was a terror attack. ISIS already calling the suspect one of its soldiers. In Paris tonight, the investigation now getting under way. ABC's James Longman with the details just coming in. Reporter: Tonight, horror in the center of Paris, after a deadly knife attack leaves one dead and injures four. Police say it all unfolded just a short time ago, near the Paris opera house when an individual with a knife began their attack, stabbing people at random. Two of the victims are seriously wounded. According to the interior ministry, a few witnesses said they heard the attacker say "Allahu akbar" before police fatally shot the assailant. Police praising the actions of the officers for quickly neutralizing the incident. Paris has been under higher security in recent years after several deadly extremist attacks. Now, forensic and counterterror police are swarming the scene, shutting down a nearby subway station as they try to determine the motive. Tonight, the mayor of Paris saying, "Our city was bruised" and that all parisians are thinking about the victim who lost their life and the wounded. James Longman, ABC news, London. ABC's Mikey Kay is the scene where the stabbing occurred. Mikey, parisians have been on edge because of recent terror attacks. Any insight on why the attacker chose this area of the city? Hi, good evening, Tom. I'm actually just feet away from where tonight's attack occurred. And moments away from the very, very busy touristy area of Paris. It's Saturday night, there are a lot of people around. Counterterrorism police behind me as we speak, Tom, trying to establish what actually happened tonight, and that additional piece of information coming in G the islamic state, claiming the attack and calling the perpetrator one of their soldiers. Once again, Tom, Paris on edge this evening. Back to you. Mikey Kay reporting live from the scene tonight. Mikey, thank you.

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