Someone fishing in Overpeck Park found a container with the remains inside on the Ridgefield Park side of Overpeck Creek late Wednesday, multiple sources said.
"It wasn't immediately obvious what it was," one said.
Bergen County Prosecutor Mark Musella confirmed that a bag was pulled from the water "containing what appeared to be a human placenta and fetal membranes.
"A determination of the exact contents of the bag is pending a final report from the Bergen County Medical Examiner’s Office," Musella said Thursday afternoon.
A search for any other possible remains was begun by a Bergen County Sheriff's K-9 unit late Wednesday and continued with dive teams early Thursday.
Businesses and other activities on the water in the area were temporarily suspended, one owner said.
Meanwhile, authorities ask that anyone who might have seen or heard something or has any information related to the incident call the Bergen County Prosecutor's Office tip line at (201) 226-5532.
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