Transcript for Desperate search in Indonesia for victims of deadly tsunami

now, to the desperate search in Indonesia for victims of that powerful and deadly tsunami. Tonight, we're getting our first look at drone footage showing the scale and scope of the devastation. And on the ground, this moment right here, impact during a concert. That terrifying wave slamming into the band and the audience. Such a chilling moment. Now, the growing concern over that volcano that triggered it all still very active tonight. ABC's senior foreign correspondent Ian Pannell on the ground now with the latest. Reporter: Tonight, more than 1,000 rescuers in a desperate race to find the missing and treat the injured after a devastating sudden tsunami hit parts of western Indonesia. And there are fears another one could crash ashore at any time. Cars and trucks hurled into buildings, piled on top of each other. And in its aftermath, the devastation it left behind. The tsunami originating in the waters between java and sumatra, where beaches are packed with tourists celebrating the holidays. Dramatic video shows a concert at a beachside resort when a wave engulfs the stage. Two members of the band and the manager were killed. The lead singer's wife missing. The military and volunteers digging through endless piles of debris. But this is also about recovering the dead. Suddenly, a man with a flashlight hears a cry in the rubble, finding a 5-year-old boy buried, terrified. But lucky to be alive. Hundreds are dead and scores missing. More than 700 buildings destroyed. From the moment part of the volcano seemed to collapse into the water, it took just 24 minutes for the tsunami to make landfall. Indonesia has an early warning system, but it hasn't worked properly in years. But it's not clear if that would have mattered. This tsunami was caused not by an earthquake, but by a volcanic eruption and underwater landslide from the 1,000-footal volcano called the child of krakatoa. Its been erupting since June. All right, Ian Pannell joins us live from the disaster zone. And Ian, they have this massive rescue operation under way, knowing full well a tsunami could hit at any moment? Reporter: That's right, Tom. We've seen rescue workers out on the roads. You can see the destruction. You see a boat that's been flung into one of these beachside shacks here. We look out to sea, it looks super calm right now, but we're told that volcano could trigger another tsunami at any point, and the warning system that people rely on still is not working. Tom? Ian Pannell for us tonight.

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