New Jersey researchers recently announced that a U.S. Marine's partial remains had been sitting in a child's rock collection for an unknown number of years.

According to officials, the story begins with the death of Marine Corps Captain Everett Leland Yager in July 1951. He was flying over Riverside County, California, when an accident occurred during a military training exercise.

The young man hailed from Palmyra, Missouri. All of his remains were thought to have been taken there, according to a press release published by Ramapo College on Monday.

"All of his remains were recovered in the Riverside County, California area and buried in Palmyra, Missouri, or at least thought to have been," Ramapo College officials said in a statement.

STRANGE ROCK UNCOVERED DURING SEA SEARCH TURNS OUT TO BE ANCIENT BATTLE GEAR

"Fast forward years later to a child who wanted to build a rock collection, and increased said collection by one during a scavenging exploration, presumably in Arizona."

Eventually, it was discovered that the rock was really a human bone – a jaw bone, it would later turn out. The skeletal remains were handed over to the Yavapai County Sheriff’s Office. 

The office, along with the Yavapai County Medical Examiner, referred the case to the Ramapo College Investigative Genetic Genealogy Center in January 2023. 

Researchers used DNA analysis to link the bone to Yager, having obtained a sample from Yager's daughter.

His daughter may be Yager's last living child, as an online obituary indicates that his son Richard passed away in 2022. He was six years old when his father died.

"It was not until March 2024 that the DNA sample from Capt. Yager's daughter confirmed a parent/child relationship, resolving the case and confirming that Rock Collection John Doe was indeed Capt. Everett Leland Yager," Ramapo College's press release read.

ANCIENT SHIPWRECKS, ARTIFACTS DATING AS EARLY AS 3000 BC UNCOVERED BY UNDERWATER RESEARCHERS

But why exactly the jawbone was found in Arizona, when the accident took place in California, had stumped university researchers.

"One theory is that a scavenger, such as a bird, picked it up and eventually deposited it during its travels over Arizona," Ramapo College said in a statement. 

The Yavapai County Sheriff's Office later told FOX 10 Phoenix that the "rock" belonged to the boy's grandfather, who found it in California and brought it back to Arizona.

"This case was a lesson in expecting the unexpected, and a testament to the power of IGG education at Ramapo College of New Jersey," Ramapo College IGG Center assistant director Cairenn Binder said in a statement. 

"The team that worked on this case at our IGG bootcamp included some truly outstanding researchers, and we are so proud of them for helping to repatriate Captain Yager's remains and return them to his family."

Fox News Digital reached out to Yavapai County Sheriff’s Office and Ramapo College for comment, but did not immediately hear back.