Witnesses said the man didn't know how to swim, ignored friends' insistence that he not go in, then went under in a deep pond on the Clifton side of the river, Clifton Deputy Fire Chief Craig Hopkins said.
Rescue teams from Clifton, Passaic and Wallington put boats in the water before a Bergen County Office of Emergency Management drone helped locate the body south of the Dundee Dam.
The victim had apparently been in the water more than an hour and a half before authorities got the call, responders said.
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