Officials say the fire happened in the 3000 block of Greenridge Drive at Westheimer.
Firefighters are working to put the fire out. It started just after noon, and quickly spread to additional units.
Two other people, including another firefighter and a resident, were treated at the scene. The resident was observed for smoke inhalation.
Firefighters can be seen working on the roof of one building, not far from where flames can be seen shooting through.
The cause of the fire is unknown.
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Major fire burning apartment complext west of Galleria