One Year After She Vanished, the Truth Is Out: Missing Scientist’s Cause of Death Revealed as Disturbing New Details Emerge About How Her Skeleton Was Found in the Wilderness

The body of a missing nuclear lab worker who vanished last year was reportedly found “skeletonized” with a gunshot to her skull in a national forest in New Mexico.

Melissa Casias’ decaying body was found in a remote part of the Carson National Forest on Monday, according to local authorities. Casias, 54, was last seen on June 26, 2025.

The body of missing nuclear lab worker Melissa Casias was found “skeletonized” with a gunshot injury to her skull.
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Thomas McNally, a former homicide detective who was investigating Casias’ disappearance for her family, told The Daily Mail that the mom-of-one’s “skeletonized” corpse was propped up against a tree – with an abandoned gun laying nearby.

McNally said that Casias’ body didn’t show any signs of animal activity or disturbance, despite being left to rot in the forest.

The investigator firmly believes that foul play was involved in Casias’ death – and hinted that her devastated family will file a civil lawsuit against the New Mexico State Police for purportedly botching the case.

Casias worked as an administrative assistant at the Los Alamos National Laboratory, created during World War II for the groundbreaking Manhattan Project, and was closely tied to US nuclear weapons research ever since.

Casia’ decaying body was found in a remote part of the Carson National Forest on Monday.
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On the day she disappeared, the married mother wiped all records from her phones before leaving them and her identification behind and walking out of her home in Ranchos de Taos, a remote community some 70 miles northeast of Santa Fe.

She dropped her husband, Mark, another Los Alamos employee, off at the facility before allegedly claiming she’d forgotten her badge and had to return home.

McNally told the outlet that Casias and her husband got into an argument over a vape pen during the commute to the lab.

The couple’s daughter, Sierra, 19, told police that Casias did return to their home, dropped off a sandwich and told her that she planned to work from home.

“She looked totally normal. Sierra said everything was fine. She didn’t look weird,” McNally told the outlet.

Casias was last seen walking alone eastward on State Road 518, some three miles from their home, around 2:20 p.m. local time.

McNally surmised that Casias “was fleeing somebody” when she disappeared.

During the investigation into her disappearance, her husband alleged that Casias “was running around with a boyfriend somewhere,” which the police “believed,” according to McNally.

Investigators believe foul play was involved in Casias’ death.
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Casias is just one of several people with links to US defense and nuclear programs who have gone missing — or died suddenly — in recent years.

Former Los Alamos employee Anthony Chavez, 79, vanished without a trace after leaving his home on foot on May 4, 2025, just seven weeks before Casias.

Monica Reza, 60, an aerospace engineer who served as the director of the NASA Lab’s Materials Processing Group, disappeared while hiking in a Los Angeles forest in June 2025.

Steven Garcia, a government contractor working for a major facility in Albuquerque, also disappeared after walking out of his home on Aug. 28, 2025, carrying only a handgun and no identification.

And retired Air Force Maj. Gen. William Neil McCasland, 68, hasn’t been seen since leaving his home in Albuquerque on Feb. 27.The FBI is now involved in the search for McCasland, who had deep knowlege on UFOs and was involved in some of the Pentagon’s most advanced aerospace research.

He also once headed up the Air Force Research Laboratory at Wright-Patterson Air Force Base in Ohio.