Federal authorities have launched an investigation to determine why a private jet tried to make an emergency landing on a Florida interstate, colliding with a vehicle and sparking a fiery crash that left two people dead.

The Federal Aviation Administration said the Bombardier Challenger 600 jet had five people aboard when the crash happened around 3:15 p.m. Friday near Naples, just north of where the interstate heads east toward Fort Lauderdale along what is known as Alligator Alley.

The FAA and the National Transportation Safety Board will investigate, with the NTSB leading the investigation. One NTSB investigator arrived at the crash site Friday afternoon, with several more expected to arrive on Saturday.

Brianna Walker saw the wing of the plane drag the car in front of hers and slam into the wall.

“It’s seconds that separated us from the car in front of us,” she said. “The wing pulverized this one car.”

Walker and her friend spotted the plane moments before it hit the highway, allowing her friend to pull over before the crash.

“The plane was over our heads by inches,” she said. “It took a hard right and skid across the highway.”

Walker said an explosion of flames then burst from the plane with a loud boom. Pieces of the plane littered the highway.

The plane had taken off from an airport at Ohio State University in Columbus, Ohio, at about 1 p.m. and was scheduled to land in Naples around the time of the crash, Naples Airport Authority spokesperson Robin King said. A pilot had contacted the tower requesting an emergency landing, saying they had lost both engines.

The pilot was cleared to land on a runway but replied “we’re not going to make the runway. We’ve lost both engines,” according to a tape of the call cited by the the Naples Daily News.

The tower lost contact, and then airport workers saw the smoke from the interstate just a few miles away, King said.

King said they sent fire trucks with special foam to the scene, and three of the five people on board were taken from the wreckage alive.

Collier County Sheriff’s Office spokesperson Adam Fisher confirmed two deaths, but said he didn’t immediately know whether the victims had been passengers on the plane or were on the ground.

According to the FlightAware aircraft tracker, the plane was operated by Hop-a-Jet Worldwide Charter based in Fort Lauderdale, Florida. The aircraft had been scheduled to fly back to Fort Lauderdale Friday afternoon.

Hop-a-Jet said Friday night that it had “received confirmed reports of an accident involving one of our leased aircraft near Naples” and would send a team to the crash site, the Naples Daily News reported.

“Our immediate concern is for the well-being of our passengers, crew members, and their families,” the statement said. It didn’t contain details of the crash.

A spokesperson for Ohio State University said the aircraft is not affiliated with the university, and they had no further information about it.

Federal authorities said a preliminary report about the cause of the crash can be expected in 30 days.