Authorities responded to the area of FM 529 and Greenhouse Drive at around 1:30 a.m. Friday in the wake of the shooting.
The victim's father-in-law says he and his son-in-law were attaching the pickup to a trailer they use to sell hot food.
As the pair was working, a man with a gun walked up and forced the men out of the truck. The gunman then drove off with the pickup.
The son-in-law hopped in a Honda CRV and started chasing the suspect. The man managed to follow the thief for a couple of miles.
However, as the chase went down Barker Cypress, the suspect opened fire.
The son-in-law drove to a gas station for help. The victim is at Ben Taub Hospital, where he under went surgery.
The shooter got away. Authorities did not immediately give a description of the stolen truck.
Follow on-scene reporter Jeff Ehling on Twitter for live updates.
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