Firefighters received notice of the fire around 11:38 a.m. Wednesday at 22 Bement Ave., said City of Poughkeepsie Fire Chief Mark Johnson.
The fire, which started in a second-floor bathroom fan, was contained to the room of origin, the chief said.
Firefighters were able to quickly douse the flames and there were no injuries to civilians or firefighters, he added.
The unit received heavy water damage, displacing the one family of three children and their mother, who are staying with family while repairs are made.
The department received assistance from Arlington and Fairview fire department and Mobile Life services.
All units were back in service by 12:02 p.m.
Jason Brodbeck contributed to this report.
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