The house was silent when a family friend dropped off 12-year-old Jonelle Matthews around 8 p.m. on a winter night.

It was Dec. 20, 1984, and she’d just finished singing Christmas carols at her Greeley, Col., school. Her father, Jim, was still out watching her 16-year-old sister, Jennifer, play a varsity basketball game. Her mother, Gloria, was headed to the airport to care for a sick parent in California, according to a story the next year in the Windsor Beacon.

When her father got home later that evening, he found the TV on and Jonelle’s shoes and shawl lying near a space heater.

But Jonelle was gone.

Her father quickly called the police to begin searching for the “strong, independent, opinionated” seventh-grader, as her sister recently described her. Fueled in part by a personal appeal from President Ronald Reagan, the case soon became a flash point amid spiking worry about childhood abductions.

It would take more than 34 years to find her. On Thursday, the Greeley Police Department announced that human remains discovered earlier in the week by workers digging for a pipeline had been positively identified as Jonelle’s.

The news brings some closure to one of Colorado’s most famous abductions, but police are still far from solving the mystery. Decades of investigation and hundreds of tips have never led to any arrests.

“This investigation remains active,” noted Greeley police, who told reporters they’re treating Jonelle’s death as a homicide.

Soon after returning home to an empty house, Jim Matthews knew something was wrong. Police quickly realized it was unlikely Jonelle would have run away into their snow-blanketed Greeley suburb about 60 miles north of Denver, although they did find footprints outside, the Denver Post reported.

Hundreds of volunteers helped police launch a massive search. A coalition of local churches organized a 24-hour prayer session. Tips poured in, but none panned out.

Jonelle happened to disappear at a time of rising national concern over kidnappings. Just six months before she vanished, the Justice Department set up the National Center for Missing and Exploited Children, a clearinghouse for leads with a toll-free hotline. As Jonelle’s parents made the television talk-show rounds, the center’s phones were peppered with tips.

In March 1985, Reagan spoke to a group of editors at the White House, urging them to “enlist your newspapers in this mission of mercy” to help find abducted children through regular stories and photos. He singled out Jonelle’s case, noting that she “would have celebrated a happy 13th birthday with her family just last month.”

As the days stretched into months and then years, tantalizing leads appeared and then evaporated. There was the South Dakota man found hoarding newspaper clippings about Jonelle, the Post reported, whose alibi checked out. The body in Florida that police soon realized had tattoos. A neighborhood truck driver bragging that he was a suspect, quickly determined to be mentally ill.

In 1994, after a decade of futility, the Matthews family declared Jonelle dead. They held a memorial service, and Jim acknowledged to reporters that his daughter was “not coming back.” But still, her family hoped for clarity.

“We had 10 years without a reason, 10 years without a motive, 10 years with no answers,” Gloria told reporters in 1994, the Post reported. “In all this time, don’t you think the person who took her has said anything to anyone? At least someone could give us evidence that would prove she is dead, or tell us where her body is, so we can bury her.”

Two years later, the story took another tragic twist. The Matthews family had adopted Jonelle, and her birth mother, a California woman named Terri Vierra-Martinez, had hired a consultant to help track her down. In late 1996, she sent a letter to Jim and Gloria Matthews, asking for a “reunion” with Jonelle.

“I was thrilled that Jonelle’s mother wanted to contact her, because Jonelle had always wanted that,” Gloria told the Greeley Tribune in January 1997. “But then I had to tell Terri that the little girl she entrusted to us is gone. . . . I had to ask myself, ‘Could I have taken better care of her?’”

The families ended up meeting, and Jonelle’s birth mother said she was grateful to know the truth. “This has put some closure in my life,” she told the Tribune. “Jonelle has always been part of my prayers, ever since she was born, and now — not knowing where she is — I’ll continue to pray for her.”

The local police periodically issued new pleas for help. Jonelle’s DNA was uploaded to a national database, and in 2013, police released an age-progressed photo of how an older Jonelle might look.

More leads came and went. In 2014, skeletal remains were found near the train tracks in Greeley. They were quickly ruled to not belong to Jonelle.

Then, on Tuesday, a crew digging in the rural land south of Greeley found human remains, Greeley police said. The Weld County Coroner’s Office later determined that it was Jonelle.

Although the Matthews family is still waiting for justice — and police are still asking anyone with information on the case to call a tip line — Jonelle’s loved ones said finding her remains was a long-awaited relief.

“I’m grateful for this closure after 34 years,” Jennifer, her sister, told the Post. “It does bring up some old wounds and some more questions, maybe, of what happened. But we’ve received so much love and support already.”

More from Morning Mix:

To win a murder conviction, police and prosecutors made up evidence and secretly paid a witness, St. Louis DA finds

Ole Miss frat brothers brought guns to an Emmett Till memorial. They’re not the first.