Transcript for Volcano erupting on Bali

mass evacuations under way tonight, including American tourists. An enormous cloud of cash and smoke seen across the island of Bali. Here's ABC's Matt Gutman. Reporter: Tonight in Bali, terrifying scenes around mt. Agung. Thisimelapse video showing ash hurtling 10,000 feet into the atmosphere. Scientists using drones already discovering a new hole in the volcano's crater. Rivers of volcanic debris and mud now fluing down the slopes. Officials declaring the highest possible threat level and expanding the danger zone to as far as six miles out, as fears of even bigger eruptions grow. 100,000 in the path ordered to flee. Many staying in evacuation centers, where they're handing out breathing masks. That ash disrupting air travel. Hundreds of flights already cancelled. Over 50,000 travelers at this top tourist destination are now trapped. We're now waiting to, I guess, go home. There is no representatives here that are going to talk to us. Reporter: And David, because the Bali airport is closed, many of those tourists, including Americans, have had to take ferries to get off the island. David? Matt Gutman, thank you.

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