New Mexico identifies remains of missing nuclear lab employee
Authorities in New Mexico have identified human remains discovered in late May as those of a Los Alamos National Laboratory employee who had been missing for nearly a year. The remains of Melissa Casias, 53, were found by a hiker in the McGaffey Ridge area of Carson National Forest on May 28, 2026, state police said in a statement released over the weekend. Casias was last seen walking eastbound along a state highway near Talpa on June 26, 2025. Police said a handgun was located alongside the remains, and the cause and manner of death have not been determined. The case is one of about a dozen involving U.S. scientists linked to space, defense, or nuclear research who have died or disappeared in recent months, the article reports. Some of those deaths have been ruled suicides or otherwise explained, but collectively the cases have fueled online speculation and drawn the attention of lawmakers and former President Donald Trump, who directed an investigation. Casias’s family stated that her remains were found in an area previously searched and that they intend to pursue answers for justice.
What’s reported
Authorities identified the remains as Melissa Casias, 53, of Taos, New Mexico, a Los Alamos National Laboratory employee.
Casias was last seen on June 26, 2025, walking eastbound along New Mexico State Highway 518 near Talpa.
A hiker discovered her remains in the McGaffey Ridge area of Carson National Forest on May 28, 2026.
A handgun was found alongside the remains, state police said.
Cause and manner of death have not been determined.
The article states the case is among about a dozen U.S. scientists linked to nuclear, space, or defense research who died or disappeared in recent months.
Casias’s husband, Mark, and daughter, Sierra, gave interviews to NBC’s Dateline program in July 2025 detailing events on the day she disappeared.
Casias’s last confirmed sighting was at approximately 2:18 p.m. on June 26, 2025, by a family acquaintance.
All of Casias’s belongings, including her purse and factory reset phones, were found inside her home, according to investigators.
Her remains were discovered about 6 miles from her home.
The family said her remains were located in an area previously searched.
Open questions
The cause and manner of Melissa Casias’s death.
Why Casias returned home the morning of June 26, 2025, and later left without explanation.
Why her phones were factory reset.
Whether the area where remains were found had been searched earlier in the investigation.
Key figures
Melissa Casias – deceased, 53-year-old Los Alamos National Laboratory employee from Taos, New Mexico.
Mark Casias – husband of Melissa, also worked at LANL.
Sierra Casias – daughter of Melissa, spoke to Dateline.
Sources: The Guardian
