Eight U.S. Scientists Dead or Missing, Tied to Sensitive Research

scientists missing –

What do a NASA researcher, a retired Los Alamos employee and multiple other lab-affiliated figures have in common — and why are so many disappearing? The list of American scientists and laboratory workers who have died or vanished has expanded again, with two additional cases now counted among eight unexplained incidents connected to sensitive research.

Cases and chronology

Frank Maiwald, a 61-year-old researcher long associated with the Jet Propulsion Laboratory, reportedly died on July 4, 2024, in Los Angeles. Officials say the cause of death has never been made public and that an autopsy was not performed. Maiwald had been with JPL since 1999 and was described as a leader on projects involving advanced satellite technology capable of scanning Earth and other planets. In June 2023 he was lead researcher on a breakthrough aimed at helping future missions detect signs of life on worlds such as Europa, Enceladus or Ceres. Despite his status as a JPL Principal, an award given to scientists ‘making outstanding individual contributions’ in their fields, there has been no public comment from the agency about his death; the only online notice of his passing was an obituary. US News Hub Misryoum reached out to Maiwald’s family and to the County of Los Angeles for comment on the circumstances surrounding his death.

The latest disappearance tied to the pattern occurred at Los Alamos. Anthony Chavez, 79 and retired from Los Alamos National Laboratory in 2017, vanished on May 4, 2025. The Los Alamos Police Department said the search for Chavez is ongoing and that no new information has been released nearly a year after he was reported missing. Chavez was last seen leaving his home in the Denver Steels neighborhood on foot; his car was locked in the driveway and personal items — wallet, keys and other belongings — were found inside the house. Although acquaintances said he enjoyed hiking, investigators noted he was not dressed for an extended outdoor trip and did not take a phone.

LANL did not respond to requests for comment on the nature of Chavez’s past work at the high-security nuclear facility. Two months after Chavez’s disappearance, Melissa Casias, 54, who reportedly held security clearance connected to the same laboratory, disappeared under similar circumstances. Her family said she chose to work from home that day, but she was later seen walking alone miles from her house without a wallet, phone or keys. Both Casias’s personal and work phones were found at home, apparently wiped and reset to factory settings.

Authorities must connect dots across jurisdictions and consider whether these cases share investigatory threads while keeping families informed and reassured.

Monica Reza, then director of the Materials Processing Group at JPL, went missing in June 2025 while hiking with friends in California’s Angeles National Forest, just days before Casias vanished. Reza had been linked through her materials work to the disappearance of retired Air Force General William Neil McCasland, who was last seen on February 27, 2026. McCasland, 68, departed his New Mexico home with only a pair of boots and a handgun, leaving behind phones, smart devices and glasses.

Security concerns

The growing roster also includes deaths among scientists. Astrophysicist Carl Grillmair, 67, was shot and killed at his California home on February 16, 2026, when he was reportedly shot on his front porch around 6 a.m. Before his death, Grillmair had been deeply involved in major space telescope missions supported by JPL and had worked on projects such as NEOWISE and NEO Surveyor. Those infrared telescope projects, designed to track asteroids, employ physics that overlap with systems used to follow satellites and hypersonic vehicles — capabilities that fall into dual-use territory.

Two Massachusetts researchers have been found dead in recent months as well. Nuno Loureiro, who focused on nuclear fusion breakthroughs in Brookline, was shot dead in his home in December 2025. Pharmaceutical researcher Jason Thomas, who had been testing cancer treatments at Novartis, went missing and was later found dead in a Wakefield lake on March 17, 2026. His disappearance dated back about three months.

Former FBI Assistant Director Chris Swecker has emphasized that even administrative staff with high clearances can be targeted because they are often “in the know” about sensitive operations. He warned that it would not be unprecedented for an administrative assistant to be singled out and urged investigators to use every resource to look for links and possible espionage activity: “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.” “I think you have to pull out all the resources necessary to look for links and look for potential espionage activities. That’s where you start,” Swecker recommended.

The pattern has drawn attention from lawmakers as well. Tennessee Congressman Tim Burchett said, “There have been several others throughout the country that have disappeared under suspicious circumstances. I think we ought to be paying attention to it.” Observers note that secrecy around classified programs can hinder public understanding and fuel speculation, while too little transparency risks eroding trust — a difficult balance for agencies handling both national security and scientific advancement.

Taken together, the mix of unexplained deaths and vanishings, the recurrence of lab affiliations, and the technical, dual-use nature of some research have prompted investigators and counterintelligence experts to treat the incidents as more than a series of isolated events. The variety of circumstances — from shootings and apparent resets of devices to people leaving home without phones — suggests multiple possible motives and perpetrators, complicating any single explanatory narrative.

As investigations proceed, officials face pressure to share more information without jeopardizing sensitive programs. Families continue to press for answers while communities and colleagues search for patterns that might reveal what is behind a troubling cluster that now includes eight names.