Transcript for New details on Paris terror attack

Now to new details on that terror attack in Paris at one of the most visited tourist sites in the world, a man armed with a hammer and knives targeting police outside notre dame cathedral. Inside, hundreds on lockdown sitting in the pews with their arms in the air. ABC's James Longman is there with the latest on all of that. Good morning, James. Reporter: Good morning, Amy. Yes, this morning the Paris prosecutor confirming that a declaration of allegiance to ISIS was found in the attacker's apartment even though the authorities had no previous knowledge of him. At 4:20 P.M. Local time Tuesday, surveillance video shows a man wielding a hammer attack an officer standing guard outside the cathedral reportedly shouting, this is for Syria. Watch again. Within seconds the officer shoots and wounds the attacker as people on the plaza scatter. Lying on the ground police say he shouted I am a sold of the caliphate. An Algerian identity card found on him. Cell phone recorded by an American shows an officer standing over the assailant. We heard the two gunshots and he had blood coming out from his leg. Reporter: As police rush to the scene at least 900 people were kept inside the 12th century church. And look at this. A startling image from the pews. People ordered to put their hands up. Nancy sudd Nancy soderbergh was there. There were accomplices so we'll search everything and that's when people got quiet and nervous. People thought there might be an attacker inside the church. Reporter: A priest said the lord's prayer to help calm people held inside for what one witness says felt like two hours. It was nice to be around people from all over the world getting through it sitting calmly together. Reporter: This morning, the attacker is in hospital being guarded by police. France has been under a state of emergency since 2015 and since then there have been four attacks on the security services. Amy. All right, such stunning images, frightening moments there, thank you, James.

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