Transcript for U.S. man who died in Nairobi terror attack was a 9/11 survivor

hour about the American who was among the 21 killed in the terror attack at that hotel in Kenya. His name is Jason spinler. World trade center attack on 9/11, only to die at that hotel in Nairobi. Surveillance cameras recording the attackers as they move in. And tonight, one new image emerging here. You're about to see the suicide bomber pacing in front of the hotel. ABC's senior foreign correspondent Ian Pannell is in Nairobi for us. Reporter: A man standing outside a Nairobi hotel restaurant, a worker walking past him, and then he designates a suicide vest. The blast too graphic to show. This surveillance footage revealing how fast a Normal afternoon in Nairobi turned to horror. This, as we learn more about Jason spindler, the 40-year-old American who lost his life in the 19-hour siege that claimed at least 21 lives. Spindler lived in Nairobi for the past several years doing humanitarian work. His office, across the street from the hotel complex stormed by at least five terrorists who detonated multiple explosives before going in, shooting innocent bystanders. Al Qaeda affiliated Al shabab claiming credit for the attack that killed spindler, who was a survivor of 9/11. His parents are heartbroken. I think he was amazing, he was my little baby. And Ian Pannell reporting in tonight from Nairobi. He's outside that hotel. And Ian, I know Kenyan officials are vowing to bring justice. But you're also learning this tragedy could have been even worse? Reporter: Yeah, that's right, David. Kenya has had to learn from past terror attacks. And miraculously, 700 people before brought out of the building behind me. But a tragedy, nevertheless, and Al shabab is threatening more attacks as the U.S. Doubles down on its strikes against the militants in neighboring Somalia. David? Ian, thank you. Back here at home now, the

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