Bergen County Prosecutor Mark Musella confirmed the death of the Fort Lee youngster, whom he said was found unresponsive by first responders at a Maple Street residence shortly after 3:30 p.m. Saturday, May 25.
She was pronounced dead at Hackensack University Medical Center a short time later.
Musella said detectives from his Major Crimes Unit and the Fort Lee Police Department are investigating the circumstances of her death, which he didn't characterize.
The prosecutor also didn't address the sudden death of the girl in Ramsey, who responders said was about to turn 15 next week.
Musella's detectives didn't go to that location, responders at the scene said.
Nothing more was known about either death late Saturday into mid Sunday afternoon.
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