At least 12 people are homeless after a four-alarm fire at a condo complex in Lake Dallas early Wednesday morning.

The fire started about 1:30 a.m. in the 400 block of Lakeway Drive near Lewisville Lake, and with in an hour was at four-alarms. Four units of the complex were gutted, displacing a dozen people.

Two Lake Cities firefighters were treated at the scene for heat exhaustion. No other injuries were reported.

About 70 firefighters from surrounding areas, including Flower Mound, Coppell and Denton, responded to the scene and crews rotated duties to try and prevent further heat exhaustion.

Hardest hit in by all the damage was Ana Leal and her four children who moved here from San Antonio just one day ago.

"Everything is gone," Leal said . "Everything I had is gone, but I have -- I have my kids."

The Red Cross is assisting all four families.

The Denton County Fire Chief says, at this point in the investigation, the fire appears to be caused by a malfunctioning air conditioner.

The Dallas Morning News contributed to this report