The fire broke out at 292 Main St. in Madison around 7:50 a.m., police said in a release.
Upon arrival, fire crews saw heavy smoke coming from the building’s roof and requested a second alarm, police said.
The fire was doused with mutual aid from the Florham Park Fire Department, Chatham Fire Department, Morris Township Fire Department, and Cedar Knolls Fire Department.
One person suffered minor injuries and was treated at the scene, police said.
Damage was limited to one apartment, and surrounding buildings remain occupied, police said.
The Morris County Fire Coordinator, Madison Ambulance Corps, Chatham Emergency Squad and New Vernon First Aid Squad also assisted at the scene, which was cleared around 9:20 a.m.
The fire did not appear suspicious and remains under investigation by the Madison Fire Department and the Madison Police Bureau of Investigation.
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