TULSA, Oklahoma - Tulsa police say about 30 percent of people whose cars are stolen are in a group known as "puffers."

It's a crime to be a puffer, but you could be one and not even realize it. 

A puffer is the person who comes outside in the morning and starts the car and leaves it running while running back into the house for a minute. A thief goes by and sees that puff of smoke coming from the tailpipe and says, that is an easy target. 

Virginia Horn was a puffer the week before Christmas. She was just running some presents into her neighbor's house for a quick minute, so she left he car running while she did so.

That's all it took for a thief to jump in her car and take off with it. 

"It's just the thought of it. What hurts the worst is my grandkids' presents were in the car, you know?" said crime victim Virginia Horn. 

A person who left their car running while they ran into a Tulsa QuikTrip recently was a puffer also. A car thief comes out, sees it and has his girlfriend passenger hop out of his vehicle into the running one and take off.

Thieves steal about 2,800 vehicles in Tulsa every year. Detectives say a third of all those happen while the car is running, the keys are in it and the owner is not around - either in a drive-way or at a convenience store.

The two most popular times for this are winter when people are keeping their cars warm and in the summer, when they're trying to keep them cool.

Tulsa gets back about 85 percent of all stolen cars, but most of the time, they're not in the same condition.

"Lot of younger kids are committing auto thefts, and they have no respect for the vehicle," said Officer Scott Dean, Tulsa Police Department auto theft.

"They wreck it, drive it hard, tear it up."

Most car thefts are a crime of opportunity. They steal a car to go from point a to point b. They run out of gas, dump that car and steal another. The last thing you want to do is make it easy for them, so don't even leave your car running with the doors locked. 

"It's not any safer," Officer Scott Dean said. "The vehicle could easily be stolen. They break a window and steal the car."

Not only is it a bad a idea to leave your car running while you're not around, it's also against the law in Tulsa. You can actually get a ticket for being a puffer.