It's the third incident in the L.A. area this month.

Today, L.A.'s district attorney pressed on whether enough is being done to stop this.

There has to be something done about this because these retail stores are going to close if they keep losing money like this.

One single flash robbery, there was an estimated $300,000 worth of merchandise stolen.

Hello, and welcome to the best case worst case.

This is Jim Clemente, retired FBI profiler, former New York City prosecutor,

and writer producer of Criminal Minds.

And Francie is not with me today, but she wishes she could be here, but she's driving somewhere between Texas and Tennessee, I think, at this point.

I don't know, something in there, in that area.

So we will see her next week when she gets back to Atlanta.

Police now say at least 30 people breaking into a Nordstrom stealing up to $300,000 in merchandise.

From Los Angeles to Miami, New York to Dallas, authorities are now witnessing a very disturbing trend.

Here's Cana with Worth.

Tonight, police in Los Angeles are searching for more than 30 thieves who stormed this Nordstrom in a brazen smash and grab robbery in broad daylight.

Mass suspects smashing display cases and making off with up to $300,000 in luxury goods before racing away and getaway cars without license plates.

All of a sudden, we saw so many people running out of the soul. We didn't know we thought it's a bomb or something.

This week, we're going to be talking with somebody who wants to remain anonymous, but he has some information about a crime and a type of crime that's been happening with more and more regularity.

And if you just heard that intro, you'll know we're talking about flash robs and that's a version of flash mobs, but it's a flash mob that rob stores and they are getting more and more common and more and more violent.

So with me today is my guest.

We'll just call him Mike.

How you doing, Mike?

Well, how are you doing today?

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