Transcript for 2 criminal investigations after 6 killed during concert in Italy

And news tonight about the deadly stampede in Italy. Police launching two criminal investigations into the chaos. Two people died. Authorities believe the club was overcrowded. The crush of people likely ignited by somebody using pepper spray. Here's Julia Macfarlane. Reporter: This was the moment the horror unfolded. Investigators are reviewing this bystander's footage of the accident at that Italian nightclub late Friday. New details tonight. Italian police tell ABC news two parallel criminal investigations are now under way. One, the suspected use of an irritant spray, such as mace or pepper spray, that is believed to have started the stampede. The other, violations of the nightclub's occupancy restrictions. The venue was only supposed to hold around 800 people. That night, almost 1,400 tickets had been sold for the event. However, it's not clear how many people were in attendance. Ticket sales are disorganized in Italy. Events are often oversold. It's one theory that investigators are looking into, as footage circulates of the disco's walkway, crumbling under the weight of so many people rushing out all at once. Police haven't confirmed reports in Italian media that a minor is suspected of spraying that irritant substance, sparking the panic, but they have told ABC news that a statement will be released tomorrow. Tom?

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