The Houston Fire Department was called to Antoine and Tidwell to the Oakwood Garden Apartments at 2:30 Sunday morning.
Fire officials say the roof of the building caved in. At least one person was taken to the hospital for possible smoke inhalation.
People who live in neighboring buildings told ABC13 they could feel the heat from the fire as soon as they stepped outside.
Firefighters say the fact that the building has a flat roof helped the fire stay contained to one side.
Still, eight units were affected by the fire and 10 have water and smoke damage.
The Red Cross arrived at the scene to provide assistance to the victims.
One of the challenges the fire department told ABC13 they're facing is that each of the units is an individually owned condominium, so there is no master list of who should be living in each one to provide to the Red Cross or to verify that everyone made it out safely.
Fire officials are investigating what started the fire.
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