Transcript for Moments before tragic church bus crash in Texas revealed in video

And we're learning much more tonight about the trablgic church bus crash in Texas that killed 13 people. New video appears to show the moments beforehand. Witnesses say, if you look closely, this is the pickup truck that caused that accident, and that the driver admitted he was texting right before impact. ABC's Marci Gonzalez with the latest on this tonight. Reporter: Tonight, disturbing new cell phone video showing that pickup truck swerving on a rural Texas highway. Somebody needs to stop him. Reporter: Just minutes before authorities say it crashed head-on into this church bus, killing 13 people onboard. You're talking about grandmothers, grandfathers. There was a husband and wife on that same bus together. Reporter: Jody Kuchler was trailing the truck for a half hour Wednesday, watching as it crossed into oncoming traffic, coming dangerously close to this truck. He's all over the road, both sides. Somebody needs to stop this guy. Reporter: Kuchler's girlfriend recording this video from the passenger seat, while he called and made a plea to sheriff's departments in two counties. He's going to hit somebody head-on or he's going to kill his own damn self. Somebody needs to get this guy off the road. Reporter: Just after that devastating crash he predicted, Kuchler says he pulled over and the 20-year-old driver, jack young, admitted to him that he had been texting behind the wheel. A claim the NTSB says it's investigating. You can't be texting and driving all over the road for that long. Reporter: Texting and driving is illegal in 46 states. Texas is not one of them. Young and just one person on the bus survived. No charges have been filed. Tom? Another violent reminder of the dangers of texting and driving. Marci, thank you.

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