But it still wasn't clear Sunday how the child got into the pool.
Westwood police say the 4-year-old boy, whose name was not released, was found by his mother around 3:15 p.m. Saturday.
The discovery came shortly after someone had called police to report that the boy was missing from his home in the Bergen County community.
Responding officers immediately started CPR on the child and took him to the hospital.
But further details on the boy's injuries have not been disclosed.
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