The National Highway Traffic Safety Administration (NHTSA) on Friday said it is investigating 2.4 million Tesla vehicles with the Full Self-Driving (FSD) software after four collisions were reported, including a fatal crash. The auto safety regulator opened the preliminary evaluation after receiving four reports of crashes in which Tesla's FSD software was engaged at times when there was reduced roadway visibility – such as sun glare, fog or airborne dust.The NHTSA said that in one crash "the Tesla vehicle ...