The body of a missing nuclear lab employee has been discovered, 11 months after she mysteriously walked out of her home and vanished without a trace.
New Mexico State Police announced that they positively identified the remains of Melissa Casias, 54, who was last seen alive on June 26, 2025.
Her body was found in the McGaffey Ridge area of the Carson National Forest, approximately six miles from the last place Casias was seen walking before being declared missing.
Police said a hiker in the forest made the discovery and that a handgun was found alongside the body. Casias’s cause of death and when she died have yet to be determined by the Office of the Medical Investigator in New Mexico.
Casias was an administrative assistant at the Los Alamos National Laboratory (LANL), a facility founded by the famed Manhattan Project during World War II. It has been tied to nuclear weapons research ever since.
Her disappearance has been linked to a string of deaths and missing person cases involving US scientists and government employees who worked at highly secretive facilities and allegedly had knowledge of sensitive topics tied to national security.
The circumstances surrounding Casias’s case were even more disturbing, as the wife and mother wiped all records from her phones before leaving them and her identification behind and walking out of her home in Ranchos de Taos last June.
It remains unclear how long Casias’s body was in the forest before it was discovered, despite the area being part of a large US Forest Service restoration project where crews have been working regularly since December 2025.
Melissa Casias worked at the Los Alamos National Laboratory, a long-running nuclear research facility, before disappearing on June 26, 2025
New Mexico State Police have stated that the body of Melissa Casias was found alongside a handgun in the McGaffey Ridge area of the Carson National Forest (Pictured)
The New Mexico State Police told the Daily Mail that investigators are still examining the scene where the body was found and are attempting to trace the gun’s origins, but it could take days before those answers are revealed.
At this time, it is unclear if Casias owned a handgun or if there is any indication as to who the weapon found near her body belonged to.
Former FBI Assistant Director Chris Swecker told the Daily Mail in March he was concerned her disappearance was part of a much larger pattern involving individuals who had access to top secret government research.
Swecker explained that Casias’s work at LANL may have made her a target for abduction, since an administrative assistant often has access to the same sensitive files their supervisors have.
‘In a classified lab, or just a high clearance lab, they would basically be in the know on what’s going on,’ Swecker said. ‘And it wouldn’t be the first time their administrative assistant has been targeted.’
However, the woman’s family and private investigators have disputed how much access Casias really had, claiming that the LANL employee lost her security clearance due to financial troubles she and her husband were having.
Casias vanished after dropping off her husband, another LANL employee, at the facility that morning, approximately 70 miles from their home.
That was when Casias’s behavior allegedly became unusual, as she claimed she would need to return home after forgetting the badge needed to access the nuclear lab.
Casias was last seen walking alone in New Mexico after dropping off her husband at work at Los Alamos National Laboratory, but not reporting for work herself
According to her husband, Mark, a superintendent at the lab, Casias had the security badge with her when she dropped him off that morning, as she would have needed the badge to get past the security checkpoints.
When Casias arrived in Ranchos de Taos, the couple’s daughter, Sierra, reportedly told investigators that her mother visited the teen’s place of work to drop off a sandwich and then said she planned to work from home after forgetting the badge.
Despite what Casias reportedly told both her daughter and husband, she returned home to drop off her work and personal phones, which the family would later find inside the house, wiped clean.
Specifically, the device showed that someone performed a factory reset on both devices, clearing all records of whom Casias may have been in contact with before vanishing.
Surveillance cameras last spotted Casias walking alone eastward on State Road 518, roughly three miles from her home, around 2.20pm local time.
The area inside Carson National Forest where her body was discovered is just five to six miles away from that state road.
In 2023, the US Forest Service approved the McGaffey Forest and Rio Grande del Rancho Watershed Restoration Project.
The project covers about 30,000 acres south of Taos, including the McGaffey Ridge area where Casias was found. Its goal is to restore forest health through tree thinning, timber harvesting, and prescribed fire to reduce wildfire risk and improve watersheds.
Workers began entering the area for active work in December 2025, starting with timber harvesting and thinning in partnership with the State of New Mexico.
Pictured: Workers harvesting timber within Carson National Forest. It is unclear how long Casias’s body was in the park before being discovered
Casias was one of four missing people with links to US defense and nuclear programs
Three other individuals in New Mexico with a connection to US nuclear facilities disappeared under identical circumstances over the last year.
Fellow LANL employee Anthony Chavez, 79, worked at the lab until his retirement in 2017, although his role there has not been made clear. He vanished without a trace after walking out of his home on May 4, 2025, just seven weeks before Casias.
Meanwhile, Steven Garcia, 48, vanished without a trace on August 28, 2025. He was last seen leaving his Albuquerque, New Mexico home on foot, carrying only a handgun and no identification.
An anonymous source told the Daily Mail that Garcia was a government contractor working for the Kansas City National Security Campus (KCNSC), a major facility in Albuquerque that plays a key behind-the-scenes role in America’s national defense.
The mysterious disappearances came to light after retired Air Force General William Neil McCasland vanished from his New Mexico home in February.
