Tennessee police are trying to determine what caused an eight-car pileup they are calling "crashfest." Clarksville Police Officer Jim Knoll says the wrecks happened at about 8 p.m. Friday, resulting in injuries to 12 people. Knoll says the wrecks started when a 2001 Dodge Intrepid swerved all over Fort Campbell Blvd., ran multiple red lights and crashed into several vehicles stopped at a red light. Knoll says the crash created "an almost pool ball-like effect" as the Intrepid sideswiped some vehicles and forced others to crash into each other. Three people were taken to area hospitals and two others were treated at the scene. Knoll says investigators are trying to determine if alcohol was involved.