Transcript for Federal investigation into deadly Tesla crash
into a deadly Tesla crash that killed two teenagers. It burst into flames after slamming into a wall in Florida. Investigators are now focusing on the fire in the car's battery. ABC's David Kerley is at a Tesla dealership this morning. Good morning, David. Reporter: Good morning, Michael. Tesla's now the subject of a few different investigations in this latest deadly incident, the investigation is looking less at the crash and more at what followed. It was a high-speed crash of a Tesla model S but it's the fire that followed which is under investigation this morning. A fire so intense bystanders couldn't help the two ft. Lauderdale high school seniors. No one could help and that crushed us. Reporter: While the teens is being mourned the fire is drawing the attention of federal investigators and regulators because this is not the first time a Tesla powered by an electric battery rather than gas has been engulfed in flames. That March accident also had a fire. ABC news has confirmed from an investigative source that the battery from that vehicle towed to an impound lot in the wreckage reignited nearly a week later. All these batteries are lithium ion and can hold a lot of power but a short or breach can lead to overheating, explosions and fires. Seen it in phones, e-cigarettes, hoverboards and many other devices. Cars contain thousands of the batteries. It is not incontinue sickly safe. The phone has one battery and a car has 7,000 batteries so the likelihood of something going wrong in a car is much more than the phone. Reporter: Tesla tells us in a statement serious high-speed collisions can result in a fire but adds that Tesla data shows a gas car in the United States is five times more likely to experience a fire. Now, it's not just the batteries that investigators want to know about in these Tesla vehicles. They also want to study how firefighters responded to these incidents and how these damaged batteries are transported after an accident. As we mentioned, Michael, one reignited nearly a week later. All right, thank you very much, David. We'll cheer that close encounter -- one family decided
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