GREELEY, Colo. — Bones found earlier this week at an oil and gas site have been identified as a 12-year-old Greeley girl who has been missing since 1984.

Just before 5 p.m. on Tuesday, a crew excavating an area in rural Weld County for a pipeline near Weld County Roads 49 and 34 1/2 found the bones. Based on evidence found at the scene, which included some clothing and a skull with dental work, investigators determined they belonged to Jonelle Matthews.

She disappeared after performing in a Christmas concert in Greeley on Dec. 20, 1984. She was last seen being dropped off at her Greeley home by a friend and the friend's father.

RELATED: 34 years after her disappearance, Jonelle Matthews remains missing

When her parents came home about an hour later, Jonelle's shoes had been left behind, the front door was open and the TV was on. 

"It's still kind of surreal," said Jennifer Mogensen, Jonelle's sister. "It's closure for me and my family but it also raises new questions now. It's sad. We're sad."

Mogensen now lives in Washington state and her parents live in Costa Rica. The family wants to know who killed Jonelle.

"Now we know that she is dead for sure and we can go on from there," said Mogensen. "Until you know for sure, there is just a little bit [of hope]."

There have been no arrests in connection with her disappearance. Mogensen also said she didn't feel rage but instead felt sympathy and "maybe some forgiveness" for the person or people responsible for what happened to her sister.

Ten years after Jonelle was last seen, both police and her family told media they were convinced Jonelle was kidnapped and murdered.

"We've never said goodbye to her and it's kind of putting a closure to it," Gloria Matthews, Jonelle's mother, said during an interview with 9NEWS in 1994 before they family held a service for Jonelle. "Because most likely she is dead. Our hearts are torn in wanting to put a closure to it and yet keeping a hope. Somehow this hope, Tuesday night, I think will kind of be buried. That thread of hope, we'll bury that hope, I think."

For the Matthews family, the past 34 years has been a nightmare filled with waiting and uncertainty. This week's discovery brings closure, but nothing will ever bring Jonelle back. 

"Every time someone asks me if I have a brother or a sister, it raises the question, how do I answer?" Mogensen said. "At my wedding, or at the birth of my son, or when I see her friends at the phase of life they are in, it makes you wonder."

Just last year, police released new video hoping it would spark new leads in the case. Anyone with information about this case is asked to contact Detective Robert Cash at 970-350-9601 or the tip line at 970-351-5100. 

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