Several lanes of the tollway had been shut down for clean up and repair. The tollway was shut down completely for about six hours Friday morning following the fiery wreck.
In a toll road surveillance video you can see only a brief reflection of the explosion from the crash along the North Belt. It happened around 2:30am on the Beltway near Antoine Drive.
Investigators believe the driver of that big rig was headed westbound on the Sam Houston Tollway when he fell asleep and veered into the concrete barrier. The rig took out an empty toll booth and went airborne, landing on top of a Ford Expedition, which was stopped while the driver was trying to pay the toll.
"We know for sure that there were two victims, one in the 18-wheeler, the other in the passenger car," said Asst. Chief Mark Herman with the Harris County Precinct 4 Constable's Office.
"It was something out of a movie, out of a horror movie. It was pretty traumatic," said eyewitness Casey Cain. "There are rubberneckers all the time, but this was something you didn't want to watch."
Cain was one of the first to stop at the scene. She shot this iWitness video with her phone. She says she and a police officer watched the flames, too great for them to do anything.
"It was just traumatic. He said there are people in there and there's nothing we can do," said Cain.
Authorities say the SUV driver had stopped to put cash in the toll plaza, and that the driver of the rig was traveling at least 45 miles per hour. They say he likely dozed off.
"The truck driver was not lined up with a lane that the truck could go through; he could have gone through EZ tag lanes or very outside lanes, wide enough to accommodate a truck," said Chief Randy Johnson with the Harris County Precinct 6 Constable's Office.
As investigators sorted through debris, crews brought in a new toll booth and concrete safety barrier and engineers with the Harris County Toll Road Authority inspect the pavement underneath the charred wreckage to make sure it is still safe for drivers.
Meanwhile, drivers say they're still horrified by the crash.
"That's real bad for the families," said another driver. "It's terrible."
There was no one inside the toll booth at the time of the crash.
Cain says she will never be able to pass by here again without thinking of what happened. It could have been her, she says. The rig sped by her just moments before the wreck.
"It's been a blessing, but it's been kinda traumatizing in a sense," Cain said.
The big rig was registered to Penske Trucking out of Dallas. A company spokesperson told us it was rented to a customer who leases from them and that the driver worked for that customer.
The spokesperson said in a statement they they "express our condolences to the families affected. Penske is still investigating this matter."
Investigators have not yet publicly identified either victim killed. They did tell us a car seat was found in or near that SUV.