Parents of Teen Murdered by Facebook Killer Share Advice to Keep Your Kids Safe Online

It's sentencing day for a cruel, calculating killer. His bizarre plot to be a hero ended in the death of an innocent teenager.

Kristine Wiley's eyes well up when she remembers her beloved daughter, Nichole. She was only 15 years old, and, like every teen, fixated with social media.

Kristine told INSIDE EDITION, "He threw her away like she was nothing. He needs to pay for what he has done."

Nichole had hundreds of Facebook friends. Among them was a guy who called himself Bryan Butterfield. But, little did she know Butterfield was really a ruthless predator named Kyle Dube.

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Dube spent weeks grooming Nichole and earning her trust through text messages. Then, one night, they arranged to meet on a dirt road just a few hundred feet from her home.

In an interview with INSIDE EDITION's Megan Alexander, Kristine said, "I just thought, she needs a little space, she needs me to trust her a little bit' so I said, 'Yeah, go ahead.'"

But when Nichole arrived at the rendezvous site, she found Dube wearing a scary ski mask.

Kyle Dube claims his plan was to kidnap Nicole, hide her in the woods. Then, when everyone was out searching for her, he would "find" her and be hailed a hero.

In a chilling handwritten confession he wrote, "All I wanted to do is prank her and scare her. I had her in a choke with my right arm over her neck. She past out and I freaked."

He drew a picture showing how Nichole scratched his face as she fought for her life. The scratches can be seen in his mugshot.

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Kristine added, "She had to fight for her life and she lost. I think that's the hardest thing, knowing the terror she must have felt. "

And get this, Dube used a pocketknife to scrape his skin out from under Nicole's nails.

Donald Macomber is a prosecutor for the State of Maine. He told INSIDE EDITION, "He kills her, scrapes her fingernails to try to eliminate any traces of his DNA, and buries her in the woods under dirt and leaves to throw off any chances of a dog finding her. Kyle Dube is truly a sociopath."

A jury agreed, deliberating for just 45 minutes before announcing their verdict

The judge announces, "Guilty of the offense of murder. Guilty of the offense of kidnapping."

Nichole's parents finally got justice for their daughter.

"The sentence on the murder charge is 60 years," said the judge in court.

Kristine added, "He's evil. I believe he is just pure evil."

As he is led away, Dube mouths 'I love you guys' to his family. He will be 82 when he gets out of prison.

Megan Alexander asked Kristine, "What do you want other teenagers to know?"

She responded, "Social media is not safe. There are really a lot of people that are dangerous on it. I don't want anybody else going through what she went through."

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