A predawn fire Monday that heavily damaged more than a dozen units of an apartment building near Norcross was apparently started by an unattended candle.

When firefighters arrived just after 3 a.m. at The Reserve at Peachtree Corners complex on Ashley Run, they found “massive fire,” with several apartments already engulfed, Gwinnett fire Capt. Tommy Rutledge said.

“Police were already on the scene, going door-to-door conducting evacuations,” Rutledge told The Atlanta Journal-Constitution.

“It appears to be an accidental fire that was sparked by a candle,” Rutledge said. “Investigators have talked to the occupants in the fire-origin apartment and they’re telling us that they may have had a candle that was unattended.”

He said one of the occupants tried to douse the fire with an extinguisher, “but it was just too far gone by that point.”

“Firefighters had to battle this blaze from the outside from the start,” Rutledge said. “They began to knock down the flames and continued to evacuate the building.”

He said no injuries were reported.

About 15 of the 20 units in the 30-year-old building were damaged.

Rutledge said about 50 firefighters battled the flames.

“We weren’t only battling the main blaze, but we were also worried about hot embers that were floating through the air that were landing on the roofs of nearby apartment buildings and in the grass and pine straw,” he said. “Firefighters had their hands full making sure this fire did not spread.”