Twenty units of a Cobb County apartment building were damaged Friday by a wind-driven fire that broke out before daybreak.

The blaze was reported shortly before 2 a.m. at the Heights of Kennesaw complex on Barrett Lakes Boulevard.

“We received several calls of heavy flames showing from the roof,” Cobb fire spokeswoman Denell Boyd told The Atlanta Journal-Constitution.

Boyd said everyone got out of the burning building safely, and the fire was under control shortly after 3:30 a.m.

“The time of morning, everyone’s asleep, and you’re always concerned that someone didn’t wake up,” she said.

Firefighters faced winds gusting as high as 37 mph as they worked to douse the flames.

Eight of the 20 units in the building sustained heavy fire damage, while the other 12 had smoke and water damage, according to Boyd.

A team of Red Cross volunteers assisted 18 adults and five children who were displaced by the fire and requested help with food, clothing and hotel lodging, Red Cross spokeswoman Sherry Nicholson said.

The cause of the fire has not been determined.