A 300,000 square foot warehouse that formerly served as a textile mill burned Sunday afternoon in Thomasville, North Carolina, local media report.

Shortly after 4 p.m. firefighters arrived to find the two-story structure fully involved with fire on the second floor, Thomasville Fire and Rescue Chief Martin S. Dailey said in a press release.

“Due to the heavy volume of fire a second alarm was requested for more fire units from other departments,” Dailey said.

Firefighters from Thomasville, Lexington, Fair Grove, Hasty, and Pilot responded to the fire scene. Fire crews from High Point and Silvery Valley staffed two Thomasville fire stations while firefighters were at the blaze.

“There were approximately 50 firefighters on the scene of the fire,” Dailey said.

Firefighters were able to bring the fire under control within several hours, during which the roof collapsed. Two firefighters were treated for dehydration and another suffered an eye injury.

Summer temperatures forced firefighters to work in a 10- to 15-minute rotations to avoid heat exhaustion, authorities said.