FBI Investigates Deaths of 10 Scientists as Officials Dispute Connection Claims
Federal inquiry into pattern of deaths and disappearances among defence and aerospace researchers reveals no evidence linking cases, despite congressional alarm.
At least 10 individuals connected to sensitive US nuclear and aerospace research have died or disappeared since 2022, prompting an FBI investigation amid congressional pressure — though federal officials and family members say no evidence supports claims of coordinated targeting.
The cases span institutions including NASA’s Jet Propulsion Laboratory, Los Alamos National Laboratory, MIT, and Caltech. The deaths and disappearances involve varied circumstances — hiking accidents, home invasions, unexplained absences — with timelines stretching from July 2023 to February 2026. President Donald Trump called the matter “pretty serious stuff” in April, while House Oversight Chair James Comer stated “It’s very unlikely that this is a coincidence,” according to CNN.
Yet officials and outside experts familiar with the cases say they have not identified evidence tying them together, per Scientific American. NASA spokesperson Bethany Stevens stated: “At this time, nothing related to NASA indicates a National Security threat.” The FBI is coordinating with the Department of Energy and Department of Defense, but no arrests or suspects have been announced.
The inquiry comes as the Office of the Director of National Intelligence’s 2026 Annual Threat Assessment warned that Russia, China, North Korea, Iran, and Pakistan are developing advanced missile delivery systems with nuclear and conventional payloads. The intelligence community has documented sustained Espionage campaigns targeting US researchers in dual-use technologies.
The Cases Under Scrutiny
The string of incidents began in July 2023 with the death of Michael David Hicks. In June 2025, Monica Reza — a 60-year-old aerospace engineer and director of NASA JPL’s Materials Processing Group — disappeared while hiking in a Los Angeles forest. Reza had patented a nickel super-alloy used in both space travel and weaponry, Fortune reported.
On February 27, 2026, retired Air Force Major General William Neil McCasland walked out of his Albuquerque home and hasn’t been seen since. McCasland commanded the Air Force Research Laboratory at Wright-Patterson Air Force Base and oversaw some of the Pentagon’s most advanced aerospace research. His wife, Susan McCasland Wilkerson, disputed espionage theories in a Facebook post: “It seems quite unlikely that he was taken to extract very dated secrets from him.”
In December 2025, Nuno F.G. Loureiro — a 47-year-old MIT physicist who led the university’s Plasma Science and Fusion Center — was fatally shot at his home near Boston. Two months later, Carl Grillmair, a 67-year-old Caltech astrophysicist who collaborated with NASA, was shot at his home outside Los Angeles. No arrests have been made in either case, according to CBS News.
Congressional Scrutiny Meets Skepticism
The Republican-led House Oversight Committee announced on April 21 it will investigate “reports that raise questions about a possible sinister connection.” Comer framed the matter as a national security priority. Trump said investigators would have answers “in the next week and a half.”
“The United States has thousands of nuclear scientists and nuclear experts… It’s not the kind of nuclear program that potentially a foreign adversary could significantly impact by targeting 10 individuals.”
— Rep. James Walkinshaw, House Oversight Committee Democrat
Two of the missing individuals worked together on an Air Force-funded research program in the early 2000s concerning advanced materials for reusable space vehicles and weapons. Beyond that shared connection and the nature of their work, no evidence links the cases. Joe Masiero, lead scientist at Caltech, told Fortune: “It’s really unfortunate to see a tragedy played out over and over again.”
Chris Swecker, a former FBI official, suggested the pattern resembles how “several foreign powers” operate, citing adversarial tactics of “abducting, blackmailing, torturing, and even killing” scientists to gain intelligence. Yet the Center for Strategic and International Studies documented historical espionage cases that relied primarily on recruitment and technical data theft, not targeted killings.
The Strategic Competition Context
The deaths and disappearances occur against a backdrop of intensifying competition in dual-use technologies. Director of National Intelligence Tulsi Gabbard testified in March that adversaries are developing advanced missile systems and nuclear delivery platforms. The 2026 Annual Threat Assessment warned that Russia, China, North Korea, Iran, and Pakistan have placed “our homeland within range.”
Foreign intelligence services have long recruited US scientists, particularly those with access to classified defence or emerging technology research. No evidence has emerged suggesting coordinated targeting versus statistical clustering in a population of thousands working on sensitive programs. The intelligence community has not released any assessment suggesting systematic elimination of personnel.
What to Watch
Trump’s timeline for investigative results has passed. Whether the FBI publishes findings or congressional hearings produce new evidence will determine if the cases remain separate tragedies or reveal security gaps requiring systemic response. Watch for any change in protective protocols at national laboratories and defence contractors — clearance procedures, foreign contact monitoring, or physical security enhancements — which would signal official concern beyond public statements.
If no connections emerge, the episode will test how quickly conspiracy theories form around pattern recognition in an era of strategic competition. The House Oversight Committee’s next hearings on researcher protection and counter-intelligence vetting will indicate whether Congress pursues substantive policy reform or political theatre. Either outcome carries implications for recruitment and retention in fields where the perception of targeting — justified or not — adds personal risk to already demanding work.