HFD District Chief Justin Gable said the call came in just after 7:30 a.m. as a warehouse fire. About 30 minutes later, ABC13's Downtown Houston cameras captured footage of smoke rising from the area.
At the scene, firefighters said they found the fire between two buildings and knocked down the flames to minimize exposure to nearby buildings.
Gable said a hazmat team and at least 50 firefighters responded to the scene. ABC13 crews reported seeing at least seven HFD trucks in the area.
Investigators said they believe the fire started in the patio area of a pizza parlor before spreading to a vacant warehouse that was previously a gym.
No injuries were reported.
The cause of the fire remains under investigation. Gable said arson investigators are looking into whether the fire was intentionally set.