Skyrocketing Prices Cause Rise In Gasoline Thefts As gas prices continue to rise, authorities are warning motorists to keep an eye on their vehicles. More specifically, on their vehicles' gas tanks. With the national average for a tank of gas nearing $5, thieves have taken to getting their fuel from other people's cars, police say. What's more is they've replaced siphoning gas with a faster, easier method, says one police chief in Washington state. "We often discover these thefts later when the owner goes to the gas station to fill up and finds all the fuel dumping out under the vehicle from the cut filler line," Hoquiam Police Chief Jeff Myers reveals. Police departments all across the country are advising motorists to invest in locking gas caps and to leave their vehicles in garages or well-lit areas with the gas cap facing a main road. Have you ever been victimized by a gas thief?