Tesla said on Friday that a Tesla Model X involved a fatal crash in California last week had activated its Autopilot system, but the driver ignored warnings to take control of the vehicle's wheel.

The logs from the computer inside the vehicle were recovered and showed that in the moments before the collision, which occurred at 9:27 a.m. on Friday, March 23rd, Autopilot was engaged with the adaptive cruise control follow-distance set to minimum.

Tesla said that the driver had received several visual and one audible hands-on warning earlier in the drive and that the driver's hands were not detected on the wheel for six seconds prior to the collision.

"The driver had about five seconds and 150 meters of unobstructed view of the concrete divider with the crushed crash attenuator, but the vehicle logs show that no action was taken," Tesla said.

The statement did not say why the Autopilot system apparently did not detect the concrete divider.

The 38-year-old Tesla driver died at a nearby hospital shortly after the crash.

The National Highway Traffic Safety Administration and the National Transportation Safety Board are investigating the fatal crash.

Autopilot allows drivers to take their hands off the wheel for extended periods under certain conditions. Tesla requires users to agree to keep their hands on the wheel "at all times" before they can use autopilot.

That accident raised questions about the safety of systems that can perform driving tasks for long stretches with little or no human intervention, but which cannot completely replace human drivers.

The crash comes soon after an Uber vehicle in Arizona in self-driving mode struck and killed a pedestrian in the first death linked to an autonomous vehicle.

Tesla defended the importance of the autopilot in its cars, saying that although it does not prevent all accidents, it makes them much less likely to occur.

"In the US, there is one automotive fatality every 86 million miles across all vehicles from all manufacturers. For Tesla, there is one fatality, including known pedestrian fatalities, every 320 million miles in vehicles equipped with Autopilot hardware. If you are driving a Tesla equipped with Autopilot hardware, you are 3.7 times less likely to be involved in a fatal accident," Tesla said.