The fire started in Nassau County around 1 a.m. Thursday, Feb. 17, at the addition to North Shore Manhasset Hospital adjacent to the hospital in Manhasset.
According to the Nassau County Police, arriving police and firefighters found an active fire in the new construction zone.
Manhasset-Lakeville firefighters extinguished the fire with the assistance of surrounding departments, police said.
The area under construction was not occupied and no injuries were reported.
The Nassau County Fire Marshal and Arson Bomb Squad Detectives responded.
An investigation into the cause of the fire is ongoing.
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