Transcript for Road rage manhunt underway across three states
Now to the road rage manhunt across three states. Here's Eva pilgrim. Reporter: Tonight, that urgent manhunt under way, in what authorities are calling a road rage killing of a teenage girl outside Philadelphia. Turn yourself in now. Every second that you are out there, you are only making this worse for yourself. Reporter: 18-year-old Bianca Roberson was just days away from her college orientation. We were proud of her, because we knew she was going to do something with her life. Reporter: Police now releasing this sketch of the suspect, and this surveillance image they say shows Roberson's car and the red pickup driven by the gunman. Tensions escalating. His car crashing after she was shot. This suspect just snuffed out the life of this young woman. Reporter: Police say this image shows the suspect driving on the shoulder to get away. Road rage and aggressive driving deaths are up, six times higher than a decade ago. Just last week in California, this motorcyclist appears to kick a car, which then swerves. A chain reaction crash ensues. There is a reward for any information leading to the gunman's capture. Police are now searching in three states. Tom? Eva, thank you. And you can learn about avoiding road rage incidents, on tonight's "20/20" at 10:00 P.M. Eastern.
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