Firefighters responded to a small but stubborn and smoky fire in a Harvard University building.
The fire in Emerson Hall was reported early Friday afternoon. The building, which opened in 1906, houses the Ivy League school's philosophy department.
The Cambridge Fire Department described it as a 3-story brick and wood classroom building.
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Acting Chief Gerard Mahoney says the building was unoccupied other than construction workers, who reported smelling smoke. There were no injuries.
Fire officials say the fire was difficult to tackle because it was in a pipe chase, a chimney-like space designed to hide pipes.
A Harvard spokesman says because of the Thanksgiving break, there were no classes or other activities in the building Friday. The school is working to determine whether it will open for classes Monday.