Police arrived at the scene on Adam Clayton Powell Boulevard around 7:42 p.m. Sunday.
They found the boy unconscious and unresponsive.
He was rushed to Harlem Hospital where he was pronounced dead.
The Medical Examiner will determine his cause of death.
Police are questioning his 26-year-old mother. The child and mother's identities have not yet been released.
So far, no charges have been filed in the case.
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