The blaze broke out in Syosset at 212 Summit Way, around 10:15 p.m., Wednesday, April 13, said the Nassau County Police.
Responding officers discovered an active structure fire in multiple attached units.
At least seven units sustained "extensive" fire and water damage, police said.
Three residents were transported to an area hospital for minor injuries associated with the fire, they added.
The Syosset Fire Department extinguished the fire with the assistance of multiple surrounding departments.
The cause of the fire is undetermined and the investigation is ongoing.
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