Firefighters responded to 172 Mansion St. at around 4:20 a.m. and encountered heavy smoke in the two-and-a-half-story home, the department said.
The fire caused significant damage to all areas of the home making it uninhabitable. Firefighters had the blaze under control by 8:51 a.m.
The cause of the fire is under investigation.
The fire department was assisted on scene by Arlington and Fairview fire districts, Mobile Life paramedics and the City of Poughkeepsie police. The American Red Cross is assisting the family with temporary lodging.
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