According to recent reports, the Department of Transportation is launching an investigation into the National Highway Traffic Safety Administration over the way in which the agency handled a recent automotive recall.

The NHTSA is being held responsible for recalling million of vehicles that had defective airbags which were installed by a Japanese auto supplier called Takata. These airbags are defenseless against moisture, which causes them to explode. The accidents related to the fault reportedly include three deaths and over 100 injuries.

“The roll out of the safety advisory by NHTSA was not optimal, but what is most important right now is that a NHTSA-led investigation uncovered a very serious defect,” said a DoT spokesperson. “Impacted vehicle owners should have their cars immediately checked by their manufacturers. This investigation is far from over and we will leave no stone unturned in the interest of public safety.”

The DoT is reportedly not satisfied in the way that the NHTSA got the word out about the recalls. According to reports, the NHTSA was aware of the airbag issue long before a recall was mentioned.

Despite the knowledge of the airbag defects, deaths due to the issue have continued. A women in Florida was killed earlier this month in a case that was eventually ruled as a murder. Some theories have emerged that suggest that the death may be due to the airbag defect.

On Monday the NHTSA posted an urgent plea on its website for owners with Takata airbags to immediately get their airbags replaced, as owners of vehicles have been directed to do in recalls over the past two years.