The teen suffered puncture wounds to her leg around 3 p.m. at South Mountain Reservation in West Orange, a spokesperson for the Essex County Sheriff's Office said.
The teen was taken to Cooperman Barnabas Medical Center.
Meanwhile, Crest Drive and the dog park were closed at the reservation until Saturday, July 1, Essex County Executive Joseph N. DiVincenzo said. He urged anyone visiting to be "extremely cautious."
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