The National Highway Traffic Safety Administration (NHTSA) announced on Saturday that U.S. authorities are investigating a crash in Florida involving a Tesla Model S that burst into flames, killing the driver. The crash occurred last Sunday in Davie, Florida.

Another accident involving a Tesla took place on Friday in Delray Beach, Florida. The NHTSA also confirmed, along with the National Transportation Safety Board, that they would be sending a team to investigate the crash, which consisted of a Tesla 2018 Model 3 crashing into a semi-truck trailer. NTSB and NHTSA are sending a team of three and a field team, respectively.

A NHTSA spokesman confirmed that there was an ongoing investigation and “will take additional actions if appropriate.”

With regards to the Davie crash, reports said the fire caused by the crash had burned the driver beyond recognition. The Tesla battery repeatedly caught fire as the care was being transported to the towing facility.

The NHTSA can demand a recall as an auto safety regulator if they believe a car possesses an unreasonable safety risk. This measure can be taken while the NTSB gives recommendations on safety.

The two agencies have been investigating a series of accidents that are targeting two issues. The first is Tesla’s autonomous Autopilot system, and the second is the batteries of electric cars catching fire after crashes. Two major crashes involved drivers crashing while in Autopilot mode in January and May of 2018 in California and Utah.

It is currently unknown whether the Tesla Model 3 was on Autopilot mode during the crash last Friday. The report stated that the car passed underneath a tractor trailer that sheared off the roof of the car before stopping three tenths of a mile later. The driver was pronounced dead at the scene.

With regards to the Autopilot system, the NTSB said in 2017 Tesla was devoid of proper safeguards. This allowed the driver “to use the system outside of the environment for which it was designed, and the system gave far too much leeway to the driver to divert his attention.”

In January 2017, NHTSA said its review found no evidence of defects in the 2016 fatal Autopilot crash. This crash would ultimately require a recall.