Remains of Colorado 12-year-old missing since 1984 unearthed by oil pipeline crew

Sheriff's deputies went to the site and, after determining the remains were human, cordoned off the area for further investigation, according to the Greeley Police Department.

"Based on the evidence found on scene and the coroner's examination of the remains, an identification has been made," Greeley police officials said Thursday in a news release. "This investigation remains active and additional information will be released as it becomes available."

The Greeley Tribune reported that it received an anonymous message Wednesday afternoon containing two photos taken at the site of the discovery. The first image depicts a hole about the size of a basketball hoop.

Above and to the left of the hole is a human skull, the newspaper reported. To the right appears to be the tattered remnants of red and blue cloth.

In the second image is a close-up of the body's lower jaw, which was separated from the rest of the skull, the Tribune reported. The teeth have braces on them.

In cable access station video recorded at the Christmas concert the night Jonelle vanished, she is wearing red and blue clothing. She wore braces at the time of her disappearance, the newspaper said.

The images the Tribune received Wednesday have not been published at the request of law enforcement and will not be published out of respect for the Matthews family, the newspaper said.

Sgt. Joe Tymkowych, a spokesman for the Greeley Police Department, told the newspaper Thursday that Jonelle’s mother and adopted father, Gloria and Jim Matthews, had been notified of the discovery.

Gloria Matthews posted the Tribune’s coverage of the find on her Facebook page.

"Sad news. Sad to have her life so brutally ended," Matthews wrote. "Thank you, Greeley police and especially Detective Robert Cash."

Gloria and Jim Matthews moved from Colorado in the decades since their daughter's disappearance and have retired to Costa Rica. The Tribune reported that for a long time, Jim Matthews was a suspect in the case.

Tymkowych declined to comment Thursday on whether or not Jim Matthews remained a suspect in his daughter's death. Matthews' biological daughter, Jennifer Mogensen, pointed out that it is common for family members to be suspects in missing persons cases.

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Mogensen, who lives in Washington state, said her father has always cooperated with the investigation into Jonelle’s disappearance. She described the discovery of her sister’s remains as bittersweet.

"We're grateful for closure, but other questions have now been raised," Mogensen told the Tribune.

Greeley police officials announced in December, on the 34th anniversary of Jonelle's disappearance, that they were renewing efforts to find her. They also released cable access video of Jonelle from the Christmas concert she participated in hours before she vanished.

"Given the significant recent advances in forensic and scientific testing methods, Greeley police (investigators) will be examining every possible forensic option available to us," officials said at the time.

KDVR in Denver reported that a friend and her father dropped Jonelle off at the family's home after the concert at Franklin Middle School, where the seventh grader was a member of the honor choir. When her parents got home around 10 p.m., the front door was open.

Jonelle’s shoes were discarded next to a chair and her stockings were tossed on the couch. There was no other sign of the preteen.

Her family held a memorial service for her in 1994, a decade after she went missing.

"We've never said goodbye to her and it's kind of putting a closure to it," Gloria Matthews said in an interview with Denver's 9 News in 1994. "Because most likely she is dead. Our hearts are torn in wanting to put a closure to it and yet keeping a hope."

Jonelle’s mother said she felt like the memorial would put an end to that hope.

"That thread of hope, we'll bury that hope, I think," she said.Jim Matthews said at the time that the service still would not bring an end to the ordeal. "It's something we feel like we'd like to put some closure to and we realize we don't have complete finality. No body, no proof (of her death)." Jim Matthews told the news station. "But still, we want to commit Jonelle to the Lord and say goodbye to her."

Jonelle was active in her family's church, Sunny View Church of the Nazarene, and had an outgoing personality, the Tribune reported in December.

Police officials said around the anniversary of her disappearance that new evidence led them to believe there was at least one person in the Greeley community who had direct or indirect knowledge about the girl’s death. They believe that person likely knew the girl and had interacted with her prior to her disappearance.

Police officials ask anyone with information about Jonelle’s death to call Detective Robert Cash at 970-350-9601 or the department’s tip line at 970-351-5100.