The fire that broke out at Hood College last week in Maryland was caused by a lightning strike, Frederick County Fire and Rescue Services ruled Wednesday.

Firefighters responded to the blaze at Brodbeck Music Hall shortly before 2 a.m. on Sept. 9. They saw flames on the roof of the three-story building.

The 75 responding firefighters knocked the fire down in about 45 minutes.

The building was unoccupied at the time and nobody was hurt.

After the fire, Hood College tweeted that the building’s “structural integrity” is OK, and it fully expected a “complete restoration.”