The National Highway Traffic Safety Administration of the United States has launched an investigation into Tesla Motors after the driver of its Model S car running on autopilot mode died after an accident, reported Reuters. The highway safety watchdog is looking at the design and performance of the driving aid installed in 25,000 sedans.

On May 7, 40-year-old Joshua Brown died after his car collided with a tractor-trailer on a highway in Florida. "When drivers activate autopilot, the acknowledgment box explains, among other things, that autopilot 'is an assist feature that requires you to keep your hands on the steering wheel at all times,' and that 'you need to maintain control and responsibility for your vehicle' while using it," the luxury car maker said on Thursday.

According to a report filed by the Florida Highway Patrol, the car went under the trailer of the truck that took a left in front of it before it went off the road, hit a fence, went across a field, went through another fence and crashed into a utility pole. The windshield of the vehicle got damaged when it went under the tractor-trailer.