The freeway had been closed for nearly 14 hours.
Around 1 a.m., the driver of the 18-wheeler slammed into a guardrail. Authorities believe that the vehicle's fuel then caught fire and spread to the box trailer, which had a load of lawnmowers.
The driver was killed.
At this time, officials do not know what may have caused him to lose control.
The 18-wheeler was the only vehicle involved.
Authorities have asked drivers to avoid the area, but those who couldn't take an alternate route ended up stuck on the freeway for hours.
"It was awful. I am supposed to be at work at 8 a.m. and I left at 7 a.m.," said driver Marcella Stone.
Her 15 minute drive from Kingwood Boulevard to Townsen took an hour.
Another ABC13 viewer shared video of her mother, who sat in the backup for six hours trying to get to work. She said her mom watched a man get out of his car and urinate on the highway because he had been stuck on the road so long.
Many said the same thing: that they could not get to work on time. With the freeway closed, the side streets quickly filled up.
"Pretty bad coming out of Kingwood. The freeway is totally closed so everyone is using the Loop or trying to find another way around," said Toni Rideout, who was caught in traffic.
Two men said they both missed appointments, one of those for the doctor, but were still trying to make it despite being four hours behind.
"I'm actually supposed to be hand digging a gas line right now to give some people some gas. Well, here we are, late," said Dan Hare.
The 18-wheeler has since been cleared. However, crews have been working to clean up debris.
Despite the delays, many of the drivers expressed sadness for the truck driver who died and his family.
A second crash involving five separate vehicles happened due to people looking at the initial wreck, police say.
People were taken to the hospital in the second crash. There's no word on their conditions.
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