The shooting happened just after 11 a.m. Thursday at a Chevron station in the 10400 block of Richmond at Rogerdale.
Video shows the shooter in a white or gray hoodie chasing the shooting victim through the parking lot, as bystanders watch as it all unfolds.
Gunman chases victim before shooting outside gas station
WATCH: Gunfire erupts outside Chevron in west Houston
TJ Parker reports from Houston Chevron shooting scene
Suddenly, the man raises his gun and fires two shots as the victim continues to run towards the front of the gas station.
The victim drops to the ground, and three more shots are fired at point-blank range. The gunman then takes off in a vehicle.
Houston police said the victim was taken to the hospital in unknown condition.
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