WASHINGTON -- The announcement comes after three fires in the last six weeks involving the electric car, which has gotten top safety ratings in crash tests performed by the National Highway Traffic Safety Administration.
Just last month, the agency said it was not planning to conduct a probe because "after reviewing all available data," it had not found evidence showing the fires were the result of a problem with the car.
In congressional testimony Tuesday, NHTSA Administrator David Strickland said the agency decided to open the investigation because of similarities between the two fires that took place in the United States.
"Two being a trend, we clearly saw some issues," he said during a hearing on an unrelated topic.
Tesla Motors CEO Elon Musk said Tuesday that the company's vice president of regulatory affairs had requested the probe on Friday to combat any doubts or fears about the fire risk.
"Given that the incidence of fires in the Model S is far lower than combustion cars and that there have been no resulting injuries, this did not at first seem like a good use of NHTSA's time," the company said on its blog. "However ... if a false perception about the safety of electric cars is allowed to linger, it will delay the advent of sustainable transport."
But Strickland testified that NHTSA independently decided to start the probe without a request from Tesla.
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