Tonya Fea, 47, of Jefferson Township "reportedly confessed," The Last Resort Animal Rescue reported.
"But, much to our horror, our worst fears were confirmed: The official [necropsy] report confirms that drowning was the cause of death," officials with the non-profit organization wrote.
The dog "was intentionally drowned," they said.
The Last Resort, which named the dog Jenny, had posted a reward that quickly ballooned to $12,000, thanks to contributions.
It also launched the hashtag #JusticeForJenny.
"We have asked the investigators to put us in contact with the two people responsible for seeing our post and calling in the tips that led them to making this arrest," the Last Resort's organizers wrote on Tuesday. "Once she's convicted we can give them their rightful reward."
It began when a Last Resort rescue member spotted the crate at the edge of in Greenwood Pond on Bonter Road on the Oak Ridge side of town on April 30.
A man had pulled the cage from the water and left it there, they said.
"The puppy was dead and ice cold and soaking wet inside the crate, lakebed vegetation hanging on the crate," the organization's Nancy Warner wrote.
Also in the cage with Jenny was a wee-wee pad and a lead-crystal ice bucket that authorities believe was used to weigh it down.
The pads had some blood on them and were stuck to Jenny's head.
Jenny was taken to the New Jersey Department of Agriculture’s Animal Health Diagnostic Laboratory, where a necropsy was conducted.
Meanwhile, township police detectives discovered that Fea had made an appointment at the West Milford Animal Hospital for a Golden Retriever puppy the same day that Jenny's body was found but didn't show up or cancel, according to court records.
Things fell into place rather quickly after that.
Fea is charged with two counts of animal cruelty and one of trespassing, authorities said.
Fea was released pending a May 22 first appearance in Central Judicial Processing Court in Paterson, Passaic County Prosecutor Camelia M. Valdes and West Milford Police Chief Timothy Storbeck said in a joint announcement.
Jenny was found in the cage at the water's edge. With her was a lead-crystal ice bucket -- which sells used for $18 to $29 online -- that authorities said helped weigh down the cage.
PHOTO COURTESY: Greenwood Lake Animal Hospital
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