Kenley Keiper said it happened Tuesday in the parking lot of the Swoyersville Borough Building.
She said the dog appeared to be a miniature Collie/Husky mix, and it was trapped inside the trunk of the sedan the entire time the man was inside the building, with the sun beating down on the car.
She said the only other thing inside the trunk was a red gas can.
Fortunately, Keiper called for help moments after snapping a photo of the car, and police were able to track down the man in just a few minutes.
Police said the investigation is ongoing, and the SPCA of Luzerne County is assisting with the case.
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