FBI Probes Deaths and Disappearances of Scientists Tied to Nuclear and Space Programs

Families who lost loved ones to accidents, illnesses and random violence now confront swirling online theories that their relatives were targeted. At the same time, lawmakers and national security officials are asking whether the pattern of at least ten cases involving researchers in sensitive fields points to foreign espionage or something far more ordinary. The tension between those two interpretations has yet to resolve.

In April 2026 the Republican-led House Oversight Committee sent formal letters to the FBI, Pentagon, Department of Energy and NASA requesting briefings on ten deaths and disappearances dating back to 2022. The FBI confirmed it is spearheading a multi-agency review to determine whether any connections exist, working with state and local police as well as NASA and the departments of Defense and Energy. According to CBS News, investigators have so far found no established links among the cases, which are scattered across years, geography and institutions.

The committee's letter cited possible risks to personnel with access to scientific secrets. Chairman James Comer stated that certain countries would have strong interest in acquiring U.S. nuclear and space knowledge. Florida Representative Anna Paulina Luna and South Carolina Representative Nancy Mace posted public warnings that amplified concern. President Trump told reporters he hoped the pattern was random and expected more information within days.

Specific cases include the February 2026 disappearance of retired Air Force General William Neil McCasland from his Albuquerque home. He left behind his phone and glasses but took a revolver on a hike. His wife posted on Facebook that he possessed no special knowledge of extraterrestrial topics sometimes tied to his former leadership of the Air Force Research Laboratory at Wright-Patterson. New Mexico state police have ruled out foul play.

In the same state, Los Alamos National Laboratory employees Melissa Casias and Anthony Chavez went missing months apart in 2025. Casias left her car, purse and phone at home after dropping her husband at work. Chavez, a retired construction foreman, left his wallet and keys behind. Detectives told CNN there were no signs of planning to leave or of foul play.

California cases cluster around NASA's Jet Propulsion Laboratory in Pasadena. Material scientist Monica Reza, who co-invented a nickel-based superalloy for rocket engines, vanished during a hike in Angeles National Forest in June 2025. Research scientist Michael Hicks died in 2023; his daughter Julia Hicks told CNN he had known medical conditions and that no federal investigators had contacted her. German-born researcher Frank Maiwald also died with no public cause released. Astrophysicist Carl Grillmair was fatally shot on his Llano doorstep in February 2026; Los Angeles County authorities charged 29-year-old Freddy Snyder, who they said did not know the victim.

Elsewhere, MIT plasma physicist Nuno Loureiro was shot dead in Brookline, Massachusetts, in December 2025 by a gunman who had carried out a mass shooting at Brown University two days earlier before dying by suicide. A separate 2022 death of Army biochemist Jude Height in Pennsylvania, officially ruled an accident after a vehicle rolled over him, has drawn renewed family scrutiny but has not been confirmed as part of the ten-case review. The suicide of antigravity researcher Amy Eskridge in Alabama that same year prompted a friend to relay her fears of targeting; her father, a former NASA employee, told NewsNation that scientists die like anyone else.

NASA issued a statement that it is cooperating with investigators but that nothing related to the agency indicates a national security threat. Joseph Rodgers of the Center for Strategic and International Studies noted the cases involve different organizations and timelines; if all the researchers had worked on one weapons system he said he would be more concerned. A former Department of Energy official put it more bluntly to CBS: people do just die.

Social media has filled with speculation ranging from foreign espionage to more exotic theories. Some families have pushed back, emphasizing the personal and scattered nature of the losses. The FBI has declined to discuss individual cases while the broader review continues. No findings have been released on whether any coordinated threat exists. The central question remains open.