The fire happened at 43-45 Blossom St. in Chelsea on the evening of Nov. 8.
“This fire had a very real chance of spreading to other buildings in a densely built residential neighborhood,” said Chelsea Fire Chief Leonard Albanese.
The Chelsea Fire Department responded to heavy fire on the upper floors of the vacant building.
The fire spread through the roof of the structure, but firefighters were able to contain it.
No injuries were reported.
The department and state police fire investigators determined that the fire started on the second floor of the building, which was vacant and had no gas or electricity.
Witnesses reported seeing a group of people running from the area before the fire was reported. Authorities have ruled the blaze as suspicious.
The Arson Watch Reward Program offers up to $5,000 for information on the blaze. The tip line can be reached by calling 1-800-682-9229.
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