The fire at Middle School at Parkside in Jackson started on the roof above the girl's locker room. The Jackson Fire Department says the fire started about 6 a.m. and was contained within the next hour and a half.
At first, they believed the fire was caused by electrical problems. But later discovered this was not the case. A janitor reported hearing people on the roof at one in the morning. He turned on the lights, and they took off.
Fire officials also found footprints and remnants of fireworks on the roof. For now, the investigation continues. The fire department says there was about $150,000 worth of damage.
School was closed for the day on Thursday, but will be back in session on Friday.