FBI Assists Probes of 10 Missing Persons, Deaths Among Nuclear, Space Lab Staff

Four current or former employees at sensitive sites have gone missing in New Mexico over roughly the last year. A well-placed government source told CBS News on April 16 that the FBI was not investigating the disappearances and deaths as part of a suspicious pattern.

The Department of Energy, which oversees NASA's Jet Propulsion Laboratory and Los Alamos National Laboratory, was looking into the matter as of April 16.

FBI spokesman Ben Williamson described the issue last week as a developing situation and said the FBI is aware and providing all assistance requested, and usually the FBI is not the lead in cases like this unless local authorities request. U.S. Department of Energy's National Nuclear Security Administration (NNSA) is aware of reports related to employees of its labs, plants, and sites and is looking into the matter, an NNSA spokesperson said.

The facilities in question combined employ more than 20,000 people, many of whom work in administrative and support roles and do not have access to secret information, according to a former DOE official. Joseph Rodgers, the deputy director of the Project on Nuclear Issues at the Center for Strategic and International Studies, said the deaths and missing persons cases are scattered across several years at different and only loosely affiliated organizations, and if all of the scientists were working on one project or weapons system, then he'd be more suspicious.

U.S. Government for more than 15 years, said the current war in Iran may factor into people's thinking, and if you were looking at a foreign adversary, Iran might come to mind because of the Iranian nuclear scientists who have been assassinated, but we're not like Iran, we have thousands of scientists and a robust infrastructure, so there would be nothing strategic Iran could achieve by taking out 10 or 20 of our nuclear scientists, as tragic as the individual deaths might be.

Of the 10 cases that have garnered speculation online, one scientist disappeared while hiking in California, five died, and four people ranging from a general to an administrative staffer went missing in New Mexico over the past year. One of the five deaths was MIT Professor Nuno Lureiro, an expert in fusion and plasma physics, who was shot and killed at his home in the Boston area last December by Claudio Neves Valente, a jealous former engineering classmate who had studied in the same program with Lureiro two decades ago.

Claudio Neves Valente, who had spent time at Brown University's engineering program, carried out a mass shooting on campus that killed two students and wounded nine others just one day before he shot and killed Nuno Lureiro. William Neil McCasland left home in February without his phone, any wearable devices or his prescription glasses, and all he had with him were a pair of hiking boots, his wallet, and a 38-caliber revolver.

Search and rescue teams led by the Bernalillo County Sheriff's Office and aided by state and federal agencies deployed drones and K9s in their efforts to find William Neil McCasland.

Air Force sweatshirt found a mile and a quarter east of William Neil McCasland's home was picked up by investigators on March 7. The FBI has been assisting local law enforcement in the search for William Neil McCasland, according to the Bernalillo County Sheriff's Office.

Investigators have so far uncovered no evidence of foul play in William Neil McCasland's disappearance, and the investigation is ongoing, according to an official in Bernalillo County. Albuquerque area officials are searching for 48-year-old Steven Garcia, who disappeared last August.

Steven Garcia worked as a property custodian for the National Nuclear Security Administration's Kansas City National Security Campus in Albuquerque.

Local police have been investigating the disappearances of two employees at Los Alamos. Melissa Casias, 53, worked at Los Alamos for years and was last seen walking alone on a highway wearing a backpack, according to a family member who has reviewed the surveillance footage.

Jazmin McMillen said Melissa Casias was an administrative assistant and did not have high-level clearance, and she is happy to see Melissa's case getting attention but has not seen any evidence linking her to any of the other cases.

Jazmin McMillen organized family search parties and has reviewed multiple pages of police documents related to Melissa Casias's case. Anthony Chavez, 78, who had held a job at Los Alamos, went missing in May of last year. Los Alamos police are asking for the public's assistance in finding Anthony Chavez.

Monica Jacinton Reza, a 60-year-old aerospace engineer who worked on rocket engines, disappeared on June 22, 2025, while hiking in Los Angeles County, California. A Facebook page devoted to the search for Monica Jacinton Reza includes pictures of her and asks for experienced hikers to help scour the rough terrain.

Carl Grillmair, a Caltech astrophysicist, was shot to death on his front porch in Los Angeles County in February.

Carl Grillmair was the recipient of the 2011 NASA Exceptional Scientific Achievement Medal and numerous NASA Group Achievement Awards, according to an obituary for Grillmair. A 29-year-old man charged with Carl Grillmair's murder was released from prison last December by a judge using an unnecessary prosecutions law.

The body of Novartis researcher Jason Thomas was recovered from a Massachusetts lake last month, three months after he was reported missing.

Jason Thomas's wife told NBC News he was distraught following the death of both of his parents last year. NASA's Frank Maiwald died July 4, 2024, at 61 in Los Angeles. Michael David Hicks, a physicist with NASA's Jet Propulsion Laboratory, died in July 2023 at the age of 59.

CBS News reviewed obituaries, statements from family members and law enforcement findings and found no links between any of the deaths.