With more folks looking to stretch their dollars by buying used cars, advocacy groups and law enforcement are warning of scams that can fool consumers into buying stolen vehicles.

The Better Business Bureau of Hawai'i and the FBI report the rise of a practice known as "car cloning" or "VIN cloning" which is similar to identity theft using Vehicle Identification Numbers. The practice involves stealing the identification number from a legitimately owned vehicle and putting it on a stolen vehicle.

Honolulu Police Capt. Sean Naito said car cloning has occurred here but doesn't seem as prevalent as in Mainland states where thieves drive cars from state to state.

Nearly 4 million used cars were purchased in May, up 23 percent over April, according to data from CNW Research. At the same time, new car sales were down 34 percent. According to the most recent numbers from CARFAX, as many as 225,000 of the 1.5 million cars stolen every year have used such cloning.

Dwight Kealoha, chief executive officer of Hawai'i's BBB said this crime has at least two victims.

"The first is the victim who had their car stolen, and the second is the unsuspecting buyer because, when the police track down the stolen car, they're going to give it back to the rightful owner and the new owner will suddenly have no car or a way to get his or her money back," Kealoha said.

A car's vehicle identification number, or VIN, is that long number usually found on the dashboard — among other places. It is a unique number that serves as a way to recognize a specific car.

The number also is used by law enforcement to track down and flag stolen cars. That's why car thieves will replace a stolen car's VIN number to match that of a car that isn't stolen.

Check the VIN on the dashboard, inside the doorjamb and under the hood against the car's title documents to see if they all match.

Sometimes the thieves will punch out a new VIN and replace the stolen vehicle's dash VIN with the new one.

The last step is selling the vehicle, usually through classified ads or informal methods. Some altered vehicles end up in auctions, or sold through unsuspecting used car lots.

Naito said buyers should try to use their common sense. "If its retail price is $20,000, and someone is offering it for $10,000 to $12,000, that's going to raise some red flags," he said.

When police are able to track down stolen cars, they will seize the car from the buyer. There is usually little recourse for the unsuspecting buyer to get his or her money back.