 The two drivers pulled over near exit 12, and after a brief argument the other driver shot Aderson and left the scene.Aderson was able to give the 9-1-1 operator he called on his cell phone a description of his assailant and the vehicle before dying at the scene.A police sketch based on Aderson's description has been widely circulated and is still posted prominently in kiosks at the freeway's rest areas.