Tesla shares plummet after investigation launched into autopilot system following series of fatal crashes

Shares down 5% as regulator says it will look at similar incidents after 11 reports of collisions with emergency vehicles

Tesla shares have fallen five per cent after federal regulators launched an investigation into the company’s vehicle autopilot feature.

The system is accused of causing almost a dozen crashes involving emergency vehicles.

By mid-morning in New York, shares in the company were trading at 5.04 per cent, down 36 points from the market opening to $681.

The National Highway Traffic Safety Administration (NHTSA) said on Monday that it was formally investigating Tesla and its partially automated driving system because it failed to spot emergency vehicles including ambulances and fire engines.

The agency says it had identified 11 crashes since 2018 in which Teslas using autopilot have hit vehicles at scenes where first responders used flashing lights, flares, an illuminated arrow board or hazard cones.

The investigation covers the entire lineup of Tesla models, the Models Y, X, S and 3 – of which there are 765,000 vehicles in the US.

The NHTSA said "the investigation will assess the technologies and methods used to monitor, assist and enforce the driver's engagement with the dynamic driving task during Autopilot operation”.

The agency will also look at "contributing circumstances" to the crashes, of which the first occurred on 22 January 2018 in Culver City, California. It involved a fire engine that was hit by a Tesla using autopilot.

Following that incident, crashes were reported in Laguna Beach, California; Norwalk, Connecticut; Cloverdale, Indiana; West Bridgewater, Massachusetts; Cochise County, Arizona; Charlotte, North Carolina, Montgomery County, Texas; Lansing, Michigan; and Miami, Florida.

The investigation could result in a recall of Tesla vehicles by the NHSTA, or bans on Autopilot being used in areas not deemed suitable to the feature.

It follows reports of crashes involving Tesla vehicles with non-emergency vehicles, and in some circumstances causing deaths, although the company has argued against claims that its Autopilot feature was to blame.

Additional reporting by the Associated Press