It happened Saturday night around 10:30.
Police were called to the Veterans Memorial Pool in Depew Park after reports that a 15-year old was drowning.
Apparently, the teen and a few friends snuck into the public pool after hours to cool off.
The boy was airlifted to Westchester Medical Center.
The area is clearly marked with signs indicating the park is closed from "Dusk to Sunrise" and the pool is entirely fenced in by a 6 foot high cyclone-type fence.
Firefighters had to use bolt cutters to open the gate around the pool.
Peekskill police were questioning two other teenagers.
Depew Park is a major recreation center for the city with the Olympic-sized Veterans Memorial Pool and a wadding pool for young children.
It also has many wooded trails, a lake and basketball courts and a playground.
The pool opened its full-time hours for the summer season on June 25.
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