Road safety regulator investigates crash involving a Model 3 that had been reportedly operating in self-driving mode.

The US road safety watchdog has launched an investigation after a Tesla vehicle reportedly operating in self-driving mode crashed into a house in Texas, killing a 76-year-old woman inside.

The National Highway Traffic Safety Administration (NHTSA) said on Monday that it had opened a probe into the fatal incident on June 19, in which a Tesla Model 3 slammed into a home near Houston.

“NHTSA is launching a Special Crash Investigation into this crash,” a spokesperson for the regulator said in a brief statement provided to Al Jazeera.

Tesla, the biggest electric vehicle maker in the US, did not immediately respond to a request for comment.

Harris County Texas Sheriff’s Office said last week that the driver told officers he had been using the Model 3’s automated driving assistance system when his vehicle left the road and struck the residence.

Police said the driver showed no signs of intoxication and cooperated with investigators following the crash.

In a post on X, Tesla CEO Elon Musk disputed reports that the vehicle had been in self-driving mode at the time of the accident.

“FSD drives slowly through neighborhood streets and this was a high speed crash!” Musk said, referring to Tesla’s Full Self-Driving mode.

Tesla’s vice president of AI, Ashok Elluswamy, also denied that the company’s technology was to blame, writing on X that the driver had manually overridden the system by pressing down on the accelerator.

“They reached a speed of 73 mph [117km/h] during the crash, and had the accelerator pressed even after the crash,” Elluswamy said.

Elluswamy did not provide a source for his characterisation of the incident.

Musk, the world’s richest man and first trillionaire, has heavily pushed self-driving technology as a core part of Tesla’s long-term strategy, predicting that 90 percent of all driving in the US will be autonomous within a decade.

While Tesla markets its Full Self-Driving mode as a key selling point of its vehicles, its current technology is not strictly autonomous, requiring human supervision at all times.

Tesla’s self-driving system has come under growing regulatory scrutiny in recent years amid reports of fatal crashes involving the technology.

In October, the NHTSA opened an investigation to determine the “scope, frequency, and potential safety consequences” of the technology following 58 reported incidents of Tesla vehicles breaking red lights or veering into oncoming traffic.

In March, the regulator escalated a probe into the performance of self-driving mode in conditions where visibility is poor due to fog, sun glare or other obstructions.

Tesla has denied that its self-driving technology poses hazards to drivers and pedestrians, arguing that it is up to 10 times safer than human drivers.