By Iris Kowalczyk · Published May 13, 2026 · Updated May 13, 2026
The FBI confirmed in April 2026 that it is coordinating a federal review of at least 10 deaths and disappearances among personnel with ties to U.S. nuclear, aerospace, and defense research. The cases span 2023 to 2026, multiple jurisdictions, and varied causes. Experts close to the underlying investigations describe no confirmed link between them. This article is the ledger, not the theory.
What the Record Currently Shows
The federal inquiry was announced after weeks of reporting by CNN, CBS News, and Newsweek through April 2026 [1][2][8]. The House Committee on Oversight and Government Reform, led by Chairman James Comer and Subcommittee Chairman Eric Burlison, sent letters dated April 20, 2026 to the FBI, NASA, the Department of Energy, and the Department of War, demanding staff-level briefings by April 27 on at least 11 individuals tied to nuclear, rocket, and aerospace research who had died or disappeared since 2023 [3].
The Bureau said it would lead coordination with the Department of Energy, the Pentagon, and state and local law enforcement. NASA spokesperson Bethany Stevens told reporters, “At this time, nothing related to NASA indicates a national security threat” [1]. CNN’s own sourced energy-security and law-enforcement experts told the network they see no obvious link between the cases [1]. That last sentence is the load-bearing one.
The investigation is, at present, a review for connections. It is not a formal task force. No charges have been filed. No suspect pool has been published. No FOIA-releasable case file has been produced. The categorical claim that “10 scientists died mysteriously” requires care: the list mixes natural death, homicide by gunshot in domestic settings, missing-persons cases without bodies, and a retiree who was last seen on foot leaving his own front door.
The Case Ledger
The entries below are restricted to cases verified in the public record as of May 2026. Each row carries name, employer, role, dates, publicly reported circumstance, and classification context where stated. Speculation goes in the notes column elsewhere. It does not go on the report.
Michael David Hicks
- Age 59. NASA Jet Propulsion Laboratory, Pasadena, California, 1998 to 2022. Comet and asteroid specialist. Served on the DART, NEAT, and Dawn mission teams.
- Died July 30, 2023. Cause of death not publicly disclosed.
- His daughter Julia Hicks told CNN her father had known medical issues and that the recent speculation had her “shaken up.” As of late April 2026, she said no one from any federal agency or elected office had contacted the family about her father’s death [1].
Frank Maiwald
- Age 61. JPL researcher. Died July 4, 2024, in Los Angeles. Cause of death not publicly disclosed [4].
Matthew James Sullivan
- Age 39. Former Air Force intelligence officer. Died May 12, 2024, in Falls Church, Virginia. Cause of death not publicly disclosed. Reportedly expected to testify in a federal whistleblower proceeding [4].
Anthony Chavez
- Age 78. Retired Los Alamos National Laboratory construction foreman; long-tenured employee until 2017.
- Last seen May 4, 2025, leaving his Los Alamos home on foot. Reported missing on May 8, 2025. Left wallet and keys behind; carried no phone.
- Los Alamos police told CNN they see no signs of foul play; exhaustive searches have yielded no evidence he was planning to leave [1].
Monica Reza
- Age 60. Engineer with Aerojet Rocketdyne; director of materials processing at NASA’s Jet Propulsion Laboratory.
- Disappeared June 22, 2025 while hiking with two companions near Mount Waterman in Southern California’s Angeles National Forest. She became separated from the group. Remains missing [4][5].
Melissa Casias
- Administrative employee with security clearance at Los Alamos National Laboratory.
- Disappeared June 26, 2025. Last seen walking alone along a road in Taos County, New Mexico.
- She had dropped her husband at the lab that morning and intended to work remotely because she had forgotten her badge. She left her belongings at home and a factory-reset phone, according to New Mexico State Police [6].
Nuno F. G. Loureiro
- Age 47. Physicist at MIT’s Plasma Science and Fusion Center.
- Fatally shot December 15, 2025 at his home near Boston [4].
Carl Grillmair
- Age 67. Astrophysicist at the California Institute of Technology; longtime collaborator with NASA programs.
- Fatally shot February 16, 2026 at his home in the Antelope Valley, California [4].
William Neil McCasland
- Age 68. Astronautical engineer. Retired U.S. Air Force major general. Former commander of the Air Force Research Laboratory at Kirtland AFB.
- Reported missing February 27, 2026, by the Bernalillo County Sheriff’s Office, which issued a Silver Alert. He left his Albuquerque home that morning. A repairman interacted with him about 10:00 a.m. His wife left at 11:10 a.m. for a medical appointment and returned at 12:04 p.m. to find him gone.
- Phone, prescription glasses, and wearables stayed at the residence. Hiking boots, wallet, and a .38-caliber revolver did not. Investigators canvassed more than 700 homes. A gray Air Force sweatshirt was recovered March 7, about 1.25 miles east of the residence [7].
- The Bernalillo County Sheriff’s Office has stated publicly that it has not developed evidence linking his disappearance to his classified work [7].
Additional names appearing on the expanded congressional list, including a former Kirtland-associated officer and earlier cases dating back to 2014, are not catalogued here pending further public confirmation of their connection to the current FBI review.
Where the Cases Overlap, and Where They Don’t
A serious analyst lays the rows side by side before drawing any line between them. The overlaps are real but thin. Three of the nine had JPL affiliations. Three were last seen in New Mexico. Most worked at institutions with some classified or sensitive footprint.
The differences are larger. The causes diverge sharply: two confirmed gunshot deaths in domestic settings; three missing-persons cases with no body recovered; one missing-person on a hiking trail; three deaths with no publicly disclosed cause, including one whose family says he had known medical issues. The timeline stretches across roughly 31 months. The jurisdictions span at least four states and federal partners. The classification levels range from a retired construction foreman to a four-star-adjacent astronautical engineer who once commanded a research lab.
In short: the cases share an aesthetic. They do not share a fingerprint.
What the FBI Has and Has Not Said
The Bureau’s public position is narrow. It is “spearheading the effort to look for connections” among the cases [6]. It is working with DOE, the Pentagon, and state and local partners. It has not announced a formal task force, named an investigation, opened FOIA-releasable records under a single docket, or characterized the deaths as related.
Several of the underlying state and local files remain active. The Bernalillo County Sheriff’s Office is leading the McCasland search [7]. Los Alamos police is the lead on Chavez [1]. New Mexico State Police is lead on Casias [6]. Local homicide divisions hold the Loureiro and Grillmair files. Federal involvement is review and coordination, not assumption.
Base-Rate Context
The cold-case discipline is to compare any apparent cluster against the expected rate. Roughly 200,000 adults are reported missing in the United States each year. Approximately 70,000 people work in the U.S. nuclear sector. Statistician David Hand, cited in Scientific American, estimates that roughly 50 people doing that kind of work go missing in a given year purely as a function of population [9].
A 2021 mortality study of 26,328 Los Alamos workers first employed between 1943 and 1980 found that 60 percent had died by the end of follow-up in 2017, which is consistent with an aging cohort. The institution’s payroll, active and retired, is large enough that several deaths per year among current and former employees is the unremarkable null hypothesis.
Hand calls this the improbability principle: in a large enough sample, unusual-looking clusters happen routinely. Medical sociologist Robert Bartholomew describes the pattern recognition as apophenia, the human tendency to find meaningful links among unrelated events [9]. For the pattern-recognition deconstruction of the conspiracy framing, see Augustus Kane’s companion piece.
A Methodology for the First 30 Days
If a working investigator received these files on Monday, the first month would not be spent ranking theories. It would be spent making the dataset honest.
Week one. Build a single normalized witness sheet per case: last seen, last contacted, last verified communications, weather conditions, vehicles present, badge swipes if employer cooperates. Establish where the timeline is firm and where it is reconstructed from family recollection. Mark every inferred fact in a separate color from every documented one.
Week two. Establish base rates. Pull DOE worker mortality data, NASA contractor mortality, and county-level missing-person counts for Los Alamos, Bernalillo, and Los Angeles counties. Calculate the expected number of cases per 18-month window in that population. Subtract.
Week three. Run a single-axis sort on each variable that has been claimed as a connector: employer, classification level, geography, cause of death, last verified communication. If a real signal exists, it survives at least one cross-tab. If the signal collapses when you sort by employer instead of by month, it was probably the sort doing the work.
Week four. Write the briefing. Include both the inculpatory and the exculpatory inference for each case. Name the two reconstructions that fit the record where the record permits two. Note explicitly which questions cannot be resolved from public sources and would require subpoena, autopsy review, or family cooperation.
A Note on Families
The Hicks family told CNN they were shaken up by the public attention. That sentence is worth re-reading. Behind every row of this ledger is a household making funeral arrangements, a spouse waiting on a search team, a daughter answering reporters who have already named her father a “missing scientist.” The investigative discipline that protects families is the same one that protects the integrity of the inquiry: name only what the record will bear, mark inference as inference, and do not promote a frame the available evidence cannot yet support.
The case-files are open. The verdict, on this page, is not yet written.
For broader background on unsolved investigations of this kind, see the parent overview at Unsolved Mysteries and Enigmas. For the pattern-recognition deconstruction of the conspiracy framing, see Augustus Kane’s companion piece.
