Transcript for Dangerous road rage incidents from across the country
Tonight a road rage battle turned deadly. A widespread manhunt for a suspect thought to have shot a teenage girl in the head after the two allegedly fought for position on a highway. As the travel heavy fourth of July weekend gets under way. We look at the alarming surge in fatal road rage incidents and how a heated moment escalates so quickly. A tragic scene two days ago, one that's become shockingly familiar. An 18-year-old girl shot and killed behind the wheel in Pennsylvania. Tonight a manhunt under way for this suspect who authorities say is armed and dangerous. This is going to come down, ladies and gentlemen, to assistance by the public. Okay? It is crucial. The family deserves this. This homicide was completely senseless, brutal and tragic. A recent high school grad who was headed to college murdered after driving home from the mall after she and this red pickup truck tried to merge into the same lane seen here in this surveillance image. The man in the red pickup truck pulled out a gun and shot her in the head killing her. This is now a murder case. She was a good girl. Honor roll student. Looking forward to going to college. Bianca's murder, just the latest example of road rage turned deadly. Across the country from this California freeway -- Call 911, Chris. To this Florida intersection. Enraged drivers. Two men caught on camera in a road rage incident involving a bat. They go at it, struggling in the middle of traffic over the weapon. Between 20006 and 2015, there's been a 500% increase in fatalities. You don't know when it's going to escalate. It doesn't take much from going to cursing to the coroner's office. It's murder. It's somebody who dies. Sitting in th vista detention facility, there's someone who's learned that the hard way. If I would have known that it ended the way it ended, I would have never ever followed him. Earlier this year Dar la Jackson a 27-year-old mother with no prior arrests was sentenced to six years in prison after pleading guilty to the voluntary manslaughter of Navy officer Zack yube. I'll commit you to the middle term of six years. The encounter between the two escalated when yube drove up alongside of her on his motorcycle and kicked the side of her car leaving a dent and shoe print. She couldn't believe he had done it. Decided to follow him to get the license plate. Another motorist captured a few seconds of the high speed chase and shortly after this clip cut off, disaster. What happens is he slows down. The driver doesn't react fast enough to that to gauge how much he's slowing down. So her nose of her car literally rolls up on to the back wheel of the motorcycle. Now ensnarled, both the car and the motorcycle siding together for 315 feet before they became dislodged. Yube hit the ground and Dar la Jackson ran over him. I won't see my daughter for a very long time. I deeply regret what happened. The country's roads and highways are increasingly snarled with traffic leaving many drivers at their breaking point. Stress levels are at an all-time high and when our stress is high, we tend to personalize what other tend to do. We view it as an insult they're cutting you off. Too often emotion takes over the wheel. You're not seeing that person head on. Because you can't see them, we tend to have more of a reaction of being more aggressive. Any angry encounter on the road can be terrifying. I almost want to stop and pullover at an exit. No. Because then she'll get out of the car. Dude, I don't know what to Do. Vanessa and her friend were headed to Reno, Nevada for a girl's weekend when their road trip turned into a nightmare. They described what went wrong. She's in the slow lane next to me and she starts coming into my lane and pushing me into the shoulder to the point where I have nowhere else to go and I have to come to a complete stop in the middle of the highway. They say things got scarier when she flipped the bird. When you add a little one finger salute, that creates crazy in a heartbeat. Just keep driving as well as you can. Even capturing her call to 911. We have a really bad emergency on highway 80. We have a vehicle that has been following us telling us that she's a cop and telling us to pullover and she's swerving us off the road. She keeps trying to hit us off the road. I'm freaking out. Dude, she's . She just hit our car. She just hit our car. She's pushing us off the road. She's coming for us. Put it in reverse. Put it in reverse, Vanessa. Suddenly this woman jumps out of the truck and runs to her window. She's in an explorer. It's a Ford explorer. She's knocking on our wind saying that she's a cop. Go ahead and go. The hardest thing was looking straightforward talking to the 911 operator. She's pounding on my window and I don't know what to do. We both said later what if she had a gun. Fortunately she didn't. She also wasn't a cop. That badge, from her job at a senior living facility. She is so . She hit us. It says next right, fuel. The 911 dispatcher tells the women to exit to a gas station and hopes the police can intercept. Okay. There's an officer right now with us. Thank you. Thank you so much, ma'am. She ultimately pleaded no contest to charging of assault with a develop. Her truck. And making threats to commit a crime resulting in death. Whatever the most -- She was sentenced to 925 days in county jail and five years probation. She declined our offer for an sboouf interview. Every second you were out tlr there, you were only making this worse for yourself and for this young lady's family. A reminder that a moment of road rage can lead to a lifetime of anger and grief. I don't think if it's even worth saying to somebody like that turn yourself in. I don't even think he cares. Nobody that cares would even do anything like that to somebody, especially somebody you don't know.
This transcript has been automatically generated and may not be 100% accurate.