Security experts warn car thieves are now using technology to steal vehicles equipped with a key fob and "push to start" system.
Tim Dimoff, President of SACS Consulting and Investigative Services, said hieves are starting to use a "two box" system to intercept and amplify key fob signals here in the United States.
The system allows crooks to capture and amplify key fob signals, while the fob is locked inside a vehicle owner's home.
Dimoff said the intercepted fab signal can then be used to unlock and start vehicles that are parked outside the owners home or apartment.
"Everybody should be made aware that if you do have a fob, it can be copied, regenerated and utilized," said Dimoff.
"What you're doing is taking the key signal, boosting it, and sending it to another booster. That booster then works on the car."
There have been cases reported in California and other parts of the country.
The National Insurance Crime Bureau has issued an alert on the system it is calling a "relay attack unit."
Roger Morris, Vice Presidents and Chief Communications Officer with the bureau said this type of technology has now made its way to the U.S. and is available to criminals online.
"The fact that it can not only open a car but start it, is very frightening," said Morris. "We tested 35 cars, it opened 19 of them, and started 18 of them."
Dimoff said if you have to keep your car parked outside your home, adding a steering wheel lock can be a good additional deterrent.
Dimoff said keeping your key fob away from the outside walls of your home, or in a shielded sleeve, purse, or wallet can help to block its signal while it's in the home.
Both Dimoff and Morris said car manufacturers can also be part of the solution.
"They're going to have to come forward, the car manufacturers, and that solution is going to be that the signal needs to be a scrambled signal, instead of what we call a straight signal," said Dimoff.