30 rounds in less than three seconds.

These things are the most dangerous things we see on the street today as far as it comes to weaponry.

Federal authorities across Texas are cracking down on these small pieces of plastic that they are calling kill switches.

It looks innocuous enough like a Lego or a connect block, but this one-inch piece of plastic is killing people.

Raising awareness on the small 3D printed parts that fit into the back plate of a gun.

They're very small, very easy to miss. And this is in the semi-automatic configuration. And all we do is turn it, and it's now into the fully automatic position.

Giving pistols the firepower of illegal machine guns. The kill switch is already responsible for deaths across the country. Somebody get Bill. Including that Houston police officer Bill Jeffrey in 2021, killed in a burst of automatic fire triggered by this device.

Houston proper is ground zero. But by far, we're seeing the most of these devices in the city of Houston.

Since then, the number of kill switches recovered by law enforcement has skyrocketed. Texas-based ATF agents have seized nearly a thousand switches since 2017, with half of those captured in just the last year.

That's partly because you can manufacture switches using commercially available 3D printers.

The parts costing as little as eight cents to produce. But ATF agents have purchased copies undercover for up to $400.

So there's a significant profit to this.

At times, federal agents say sellers are even turning to social media to sell these products.

Just this device right here is considered a machine gun. It does not have to be onto a fire arm.

The possession of one carries a penalty of up to 10 years in prison.

Switch-equipped guns fire faster than military-grade M4s. We cannot have our streets turned into war zones.

A battle to keep communities safe from these illegal devices that can turn lethal.

Cathy Park joins Top Story tonight. Cathy, we saw there in your story how quickly shots can be fired when a switch is installed. What are officials doing, though, to make these switches aren't being used in the first place?

Hey, Tom, that's a great question. A big part of this federal initiative is actually to work with state and local partners, educating them, because oftentimes we're told these departments don't even realize the switches are in their gun vault. As you saw in the story, these switches are extremely small, about an inch in size, and they can blend in easily when they are installed correctly in a firearms. In fact, if they are the same color as the gun, they can be overlooked pretty easily. So federal officials will be working with local crime stopper programs and offering cash rewards for any information leading to the arrest of an individual who may be in possession of these switches or are manufacturing them. Tom?

All right, Kathy Park for us. Kathy, we thank you for that.

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