SPRING LAKE, Mich.—A gas station cashier in western Michigan says she thought she’d be able to stop a fuel thief by jumping in his car. Nope, he just kept driving.

Twenty-one-year-old Jessica Sudy says she had already seen the same motorist leave the Spring Lake gas station twice without paying. On Wednesday she says she wrote down his license plate number, but then the man grabbed the paper from her and fled with more than $30 worth of gas.

The 4-foot-9 cashier says thefts cut into her monthly bonus. So she hopped inside the car as the man drove off.

She got out a block away.

Police are seeking charges against a 22-year-old suspect tracked down through vehicle registration. And Sudy has gotten lectures from police, her manager and her mother.