(KMOV) -- Wednesday night it reached $3.29 in Missouri and $3.49 in Illinois. When this happened before, some drivers resorted to stealing gas. Now, that's happening again.
We checked with police, who tell me that they're already seeing people driving off from gas stations without paying.
As the prices at the pump climb higher, so does the concern for thieves targeting your tank. Some of you might remember the gas crisis of the 70s when drivers would come out to find their gas tanks on "E" -- siphoned off by a thief. Police say it's an old trick that's making a comeback.
"She had just filled up the day before, so when she got in the car, she was down to a quarter of a tank," Esther Stanley, a resident of Lake St. Louis, said about her daughter's car.
Police are looking for tips about the person who drained the gas tank and took off.
"We've been hit probably a couple of times," Stanley said. "The last time was when gas got really high."
Both times, Stanley's cars were parked outside. It fits the trend Lake St. Louis Police have identified before, and they're starting to see it again.
"A lot of people were parked in the street, and [thieves] would pull up alongside their cars and siphon the gas from the victim's car into their car," Capt. Chris DiGiuseppi said.
"It makes you very angry because you try to take care of your stuff and make sure you have gas so when you're ready to go, you're ready to go," Stanley said.
Police say gas thieves can be hard to catch, but that you can help by being aware of who's around your neighborhood.
"Everyone needs to be vigilant, watch for it and take appropriate precautions," Capt. DiGiuseppi said.
The bottom line: don't make it easy. Police recommend buying a locking gas cap. For about $12, you might save yourself the price of a fill-up.
"In the cases that we've seen, it was easy access because they want to get in and out quickly," Capt. DiGiuseppi said.
"We used to have one on our other cars," Stanley said. "Now we've seriously considered getting locks for all of them."