Deputies with the Harris County Sheriff's Office said the attack happened at a Shell gas station at 16955 W. Little York Road on July 18.
On Wednesday, deputies released surveillance footage that shows the driver of a black truck stop in front of the gas pump and march over to the driver's side of another car.
In the other car, the 80-year-old opens his door, and the two men appear to exchange words before the suspect aggressively throws something at the victim and goes back to the truck.
The victim's vehicle moved forward a few feet, with the door still open, before the 80-year-old got out of the car and appears to throw the item back at the suspect.
The suspect appears to punch the victim before he falls to the ground, landing on his side.
Deputies say the 80-year-old broke his hip.
A bystander and the victim's passenger approached the 80-year-old on the ground as the suspect drove off.
Deputies didn't release the make or model of the suspect's truck and are asking the public for help in identifying the alleged attacker.
Authorities urge you to contact the Harris County Sheriff's Office by calling 713-221-6000 or Crime Stoppers of Houston at 713-222-TIPS (8477) if you have any information related to this investigation. Tipsters can also contact Crime Stoppers by submitting an online tip anonymously or through the Crime Stoppers mobile app.
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