Transcript for French police shoot and wound man who attacked them outside Notre-Dame

tonight with the newest terror attack, this time in Paris. Tourists trapped inside the notre dame cathedral. We have exclusive video tonight of the attacker, targeting a police officer outside the cathedral. Inside, look at this. Hundreds trapped. You can see their hands in the air. So far, it appears the attacker was working alone but tonight, Paris is on edge and ABC's John Longman leads us off from the scene. Reporter: Panic today in the heart of Paris, throngs of tourists sent running, as shots ring out in front of one of the world's most iconic cathedrals. The drama began at 4:20 P.M., surveillance cameras trained on the crowded plaza in front of notre-dame capture the moment an attacker lunges at three police officers, striking one of them with a hammer. One of the other officers draws his gun and fires. The attacker falls to the ground. You can see the man lying on the ground here, an officer standing over him, the cellphone video recorded by an American tourist, Kyle riches. We heard two gunshots and so at that point, my wife and I ran away to the corner, and then we turned around and saw a guy on the ground who was bleeding. Reporter: As police rushed to the scene, frightened tourists scatter. You didn't know what was happening, people running towards us, so you have to keep running. Reporter: Inside the ancient cathedral fear and confusion, people told to put their hands over their heads. Nancy Soderberg, a former American ambassador to the U.N., was in one of those pews. They made us put our hands up, saying that there may be accomplices there so we're going to search everything. And that's when people got really quiet, and very nervous. And that was kind of scary, because people thought there might be one of the attackers inside the church. As police officers methodically check each pew, priests try to soothe the crowd, reciting the lord's prayer in English and in French. This mother and daughter from New Hampshire were also inside the cathedral. It was nice to be with people all around the world. It was two hours before they were allowed to leave. Tonight the attacker is recovering in the hospital. His identity still unconfirmed, he was carrying the I.D. Card of an Algerian student, sources tell us he is 40-years-old. And there wasn't just a hammer, he was armed with several kitchen knives. A top French government official noting a different kind of terror. "We have passed from a very sophisticated terrorism," he said, "To a terrorism where any instrument can be used for attacks." Let's bring in ABC's John Longman if Paris tonight. He's joined our team of foreign correspondents. John, great to have you on the team. The police officer attacked is in the hospital refer covering tonight. Not the first time police officers targeted in France if. Reporter: That's right -- David. Just in April, that a police officer was shot in the head on the champs-elysees here. ISIS is specifically asking its followers to target law enforcement.

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