Transcript for 6 dead in a stampede at an Italian night club

Next to the panic at a packed Italian nightclub. At least five teenagers and a mother crushed to death. Dozens hurt in that stampede. ABC's Julia Macfarlane with what may have set the crowd off now. Reporter: Tonight, Italian police reviewing this footage. Watch as this railing begins to break, and then chaos as the structure gives way completely. Dozens falling on top of each other. It happened just outside a nightclub in central Italy, as hundreds of people left the venue after a stampede inside. Local police say five minors, and one mother were killed, crushed in the chaos. Dozens injured. The crowd filled with mostly teens on hand to watch a popular Italian rapper. "They were falling and trampling over each other, also having a hard time breathing," this young man said. Tonight, police investigating claims that someone in the crowd used an irritant spray, triggering the stampede. Police are also looking into whether the club was over its legal capacity, saying the venue sold tickets to nearly twice as many people than it was permitted to hold. Tom. Julia, thank you. Back here at home to the

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