The building at 463 Gore Road was being remodeled to house apartments.
Ashtabula township fire department also responded.
The building burned to the ground.
A house near the building had its vinyl siding melted by the extreme heat.
Spectators were kept some distance away from the scene because of the possible danger of exploding fireworks or ammunition according to Assistant Chief Steve Sanford
A State Police Fire Marshall will be on the scene tomorrow to investigate.
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