YMCA staff were tending to the boy, who "was unresponsive and cyanotic" when Officers Robert Schlossberg and Michael Scalise around 12:30 p.m., Lt. Joseph Soto said.
The officer conducted CPR while clearing the boy's airway of obstructions, Soto said.
"The boy began to breathe on his own and was transported to the hospital by the Wyckoff Ambulance Corps and paramedics from Valley Hospital," the lieutenant said.
Wyckoff police extended "best wishes for a full recovery to the boy and his family," Soto said.
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