Heavy fire and smoke had engulfed most of the complex when between 40 to 50 firefighters first arrived on scene, according to officials with the Montgomery County Emergency Services District (ESD) 1. 

No residents were injured in the fire, Montgomery County ESD 1 Fire Chief Jason Oliphant said.

"We did have one firefighter that was injured but he has been checked out by EMS and has been released at this time," Oliphant said.

One of the residents had just moved into the complex the day before. Justin Sweeten moved to Houston from Fort Worth Monday. "It went so fast," Sweeten said. "...Smoke was just billowing in. I turned my back and the roof behind me (another unit) was just engulfed in flames."