In June 2013, TODAY national investigative correspondent Jeff Rossen reported on a wave of auto thefts involving a high-tech gadget giving criminals full access to your car.

Police were stumped. But now officials say they may have solved the mystery. "It certainly could be a factor in some of the increase in thefts we've seen recently," said Roger Morris of the National Insurance Crime Bureau.

With Rossen producer Jovanna Billington playing the part of car theft victim, Rossen and Morris demonstrated how the device works. Billington parked her car in a parking lot, locked it and walked away.

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What she didn't see was a "suspect" played by Morris, trailing behind her with the device in hand. Within seconds, the device cloned the signal of her car's key fob.

Rossen's smaller device picked up that signal, and in effect, became the key to Billington's car. It took him only seconds using it to open her car and start it.

And that's not all. Experts were able to use the same device to break into and even start 17 different makes and models of cars.

The Alliance of Automobile Manufacturers, an auto industry association, told NBC News that "protecting vehicle access and security continue to be top priorities" and that "automakers have been working on multiple fronts" to address security and enhance it.

"Technology has been driving down the theft rate for years, and now thieves are using technology to perhaps drive it back up again," Morris said. He suggested that motorists concerned about the device "park in a crowded area at least so it lessens the chance. And if you see someone suspicious around there, have second thoughts and maybe alert the police."

So why does this technology even exist? The insurance experts bought their device from a company in Europe. That company says it's meant to be used as a tool to test how vulnerable different cars might be, and they won't just sell it to anyone.

Still, officials worry that clever criminals will find a way and likely already have.