The California fire department reported that a Tesla driver was killed early Saturday morning when his vehicle collided with a fire truck parked on an interstate highway.

The Autopilot driver assistance system in Tesla vehicles, including the Tesla Model S, is under investigation by U.S. authorities following collisions with parked emergency vehicles, Reuters reports.

 One of Tesla's passengers was in severe condition after being transported to the hospital, according to a tweet from the Contra Costa County Fire Protection District,

The fire department reported that the truck was blocking lanes on Interstate 680 due to an earlier accident.

Meanwhile, the investigation of Tesla's Autopilot and related car technologies "remains open and ongoing," said a statement released on Thursday by the National Highway Traffic Safety Administration.

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Four California Firefighters Were Injured Following the Tesla Model S Accident

Firefighters on board the ladder truck suffered minor injuries, said Assistant Chief Tracie Dutter.

The agency uploaded multiple images on its Facebook page depicting the damaged Tesla Model S and preparing the $1.4 million truck to be towed, per Fox News.

The vehicle was positioned diagonally across the northbound lanes of the motorway with its lights on to shield emergency workers from oncoming traffic as they dealt with an earlier accident with no reported injuries, Dutter stated.

Officer Adam Lane of the California Highway Patrol stated that it was unclear whether the Tesla driver was impaired or whether the car was using any of its Autopilot or driver assistance features.

The Accident Could Be Another Tesla Headache if the Car Was in Autopilot Mode

Tesla could be in for more trouble if it comes out the Tesla driver on California interstate highway was using the Autopilot, which has previously been heavily criticized, The Daily Mail says.

The Tesla Autopilot system's interaction with emergency vehicles is the subject of an investigation by the National Highway Traffic Safety Administration.

Reports of 14 accidents involving Tesla cars in recent months, several of which were linked partly to Autopilot technology, led to the recall.

The Tesla Model S was among the Tesla vehicles recalled last week when the company stated it would recall 363,000 vehicles owing to possible concerns with their self-driving features.

The vehicle can "exceed speed limits" because of the Full Self-Driving Beta software, according to a statement from the National Highway Traffic Safety Administration on Thursday.

It is further asserted that the vehicles' movement through junctions in an unauthorized or unpredictable manner raises the risk of a crash.

There has been no word on injuries or fatalities associated with the recall. Tesla has promised to issue a free software update for affected vehicles via over-the-air (OTA) transmission.

After reading about the allegations, Tesla CEO Elon Musk took to Twitter to comment, writing, "The word 'recall' for an over-the-air software update is anachronistic and just flat wrong!"

Models of Tesla vehicles manufactured as far back as 2016, including Tesla Model S, are included in the massive recall that affects 362,758 cars.

Although Tesla disagrees with the NHTSA's diagnosis of the issue, the agency's documents indicate that the company is carrying out the recall.

The online software upgrade will fix the issue in the coming weeks.

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Written by: Bert Hoover

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