Transcript for 6 dead after stampede at Italian nightclub

We want to turn to thatsterfying scene in Italy. A stampede at a nightclub left six people dead and more than 50 people injured. People have launched two investigations. James Longman has the latest. Reporter: It's total chaos as revelers rush out of this Italian nightclub, and then -- horror. As the structure gives out. Sending dozens falling, crushing others below to death. Investigators are reviewing that bystander's footage of the accident from early Saturday trying to figure out how the accident happened which left six dead and dozens injured. Italian police telling action news two parallel criminal investigations are now under way. One, whether the club was dangerously overcrowded. Legally, the venue is only supposed to hold around 800 people, but almost 1,400 tickets had been sold for the event that night, but it's unclear how many were actually there. Ticket sales are disorganized in Italy, and often oversold. That's one theory being looked into, and the other is the suspected use of a chemical inside. One saying pepper spray may have started it. Some people saying they struggled to breathe after this. The youngest victim just 14 years old, and there are reports that it was also a minor who is suspected to have sprayed that substance, but police have yet to confirm that. What a tragedy. Thanks very much.

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