An abandoned elementary school in DeKalb County was heavily damaged Thursday by a predawn fire, but no injuries were reported.

DeKalb fire Battalion Chief Henry Jenkins said the fire broke out around 2:45 a.m. in the former Hooper Alexander Elementary School on Memorial Drive at Rupert Drive. The school closed in 2008, and was boarded up.

“We don’t know what started it or where it started,” Jenkins told The Atlanta Journal-Constitution. “When we got here, it was well-involved.”

Jenkins said that since the building was abandoned, fire crews battled the blaze from the outside, using three ladder trucks to pour water onto the fire from above in the subfreezing weather.

“We ended up calling a second alarm for manpower and because of the weather,” Jenkins said. “The water is starting to freeze up on the ground and that’s our biggest concern.”