Transcript for Investigation intensifies into the Paris airport attack

Heading overseas, we're learning more about the man at the center of a deadly confrontation with soldiers at a Paris airport. Here's lama Hasan. Reporter: Tonight, new details emerging about the Paris airport attacker, who created a scene of chaos and fear. All of a sudden, we just heard people running and screaming, it was really scary, I've never been that scared in my life. Reporter: Officials now saying the suspect, ziyed Ben belgacem, was radicalized during a 2012 stay in prison. In Saturday's assault, he shouted, "I'm here to die for Allah," when attacking a female soldier before being gunned down by two fellow officers. Reporter: This witness describing the terror. "We heard two, three, four gunshots, then five. We thought, it's an attack." Reporter: His father, speaking out, saying his son was not a terrorist, blaming drugs and alcohol for his violent behavior. Ever since the deadly terror attacks in 2015, soldiers patrolling in small units like this one were mobilized across the city at major tourist sites and airports, designed act as a layer of protection. But they've also become prime targets. European airports' unsecured areas now seen as a soft target after the 2016 coordinated attacks in Brussels and the gun attack at an airport in Turkey. And we're just learning, the autopsy results, that the man had alcohol and drugs in his blood. This, as investigators are still

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