Stockbroker John Ozbilgen, 29, left a note for his parents before committing suicide in November, weeks after Stephanie Parze was reported missing , Gramiccioni said during a news conference in Freehold.
"He stated that he had had enough and that he could not do life in prison,' the prosecutor said. "He also admitted that what his parents would hear in the news was true, except for charges of possession of child pornography.
"He acknowledged that he had dug himself a deep hole and this was the only choice," he said.
Ozbilgen didn’t say where he disposed of the remains or how Parze was killed, Gramiccioni said.
A medical examiner would have to make that determination, after her body was found by two teens in Old Bridge, he said.
Gramiccioni was joined at Monday's news conference by, among others, parents Edward and Sharlene Parze.
"Our lives are never going to be the same," Edward Parze said. However, Stephanie’s home, she’s coming home, at last, where she belongs. And we have God to thank for that."
Parze, whose family lives on Route 33, didn’t show up for her nannying job the next day after returning to her late grandmother’s house following a night out in New Brunswick with her mom and sister to see medium Cindy Kaza’s show, authorities said.
Police said her car and cellphone were left at her grandmother’s house. No signs of forced entry or a struggle were found, they said.
Authorities pegged Ozbilgen as the suspected killer since early November, soon after Parze was reported missing on Oct. 31, Gramiccioni said.
The prosecutor cited Ozbilgen's "on and off nature of his relationship with Stephanie" and "several social media messages," among other evidence.
More than 50 search warrants were executed at 10 locations, he said -- including five different times at Ozbilgen's home.
Investigators arrested Ozbilgen, after finding child porn on his phone. A judge later ordered him released.
A few days later, Ozbilgen hanged himself in his parents’ garage, authorities said.
The Parze family was aware of what was happening from the very beginning, Gramiccioni said, but "we were still working on finding Stephanie and we were maintaining an active homicide investigation."
For that reason, the evidence against Ozbilgen was withheld until Parze's body could be found, he said.
Authorities also canvassed "hundreds of acres" in Monmouth, Middlesex and Ocean counties, as well as on Staten Island, Grammicioni said.
Throughout it all, the prosecutor said, Stephanie's parents were "the picture of grace."
"Of course, all of us hoped and prayed that we would find her alive despite the odds and evidence in this case," Gramiccioni said. "At least now, we hope, the Parze family can bury their daughter in peace."
As Edward Parze noted, "thousands of dedicated people participated" in the search for his daughter."I’ve never seen such a devoted group of committed people in my life," he added.
On Sunday, two teens -- one 17, the other 18 -- were walking south on Route 9 just south of Old Mill Road when they found the body.
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