Two teens were killed in Florida Tuesday night when a 2014 Tesla Model S went off the road, ran into a concrete wall, and burst into flames—and now the National Transportation Safety Board is investigating, making this the fourth accident involving Tesla vehicles that the NTSB is probing, the Wall Street Journal reports. While two of the other accidents involved Autopilot, Tesla's driver assistance feature, the NTSB doesn't anticipate Autopilot being part of this probe; rather, it's focusing on the fire and the electric car's lithium-ion battery. One of the other NTSB investigations also focuses on a battery fire.
Local police believe speed was a factor in Tuesday's crash, which happened on a stretch of roadway locals call "Dead Man's Curve." A yellow light warns drivers to slow to 25mph before a sharp left curve in the road; a witness tells ABC News the car appeared to be going 50mph to 60mph when it crashed. A third passenger was thrown from the vehicle but survived. "Everything we have seen thus far indicates a very high-speed collision and that Autopilot was not engaged," says a Tesla spokesperson, noting that high-speed crashes can be fiery "regardless of the type of car." A spokesperson tells USA Today that "had Autopilot been engaged it would have limited the vehicle's speed to 35mph or less on this street." (Read more Tesla stories.)