A 5-year-old boy drowned in the bathtub of his Chelsea home Monday night, police said.
The boy was left alone in the tub at about 10:30 p.m. while his mother went to answer the phone, police said.
When she returned, she found her child unconscious in the tub.
Emergency responders rushed the boy to Bellevue Hospital, where he was pronounced dead.
The boy's parents were questioned and released. Police said there were no other signs of trauma on the boy.
The medical examiner said an autopsy proved inconclusive, and there will be further testing and investigation.
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