President Donald Trump has been briefed on a growing list of deaths or disappearances of U.S. experts in advanced space, defense, and nuclear fields in recent years, calling it "pretty serious stuff."
The White House intervention comes after speculators online moved some lawmakers to call for closer scrutiny of the cases, which include a retired Air Force general’s disappearance and a leading astrophysicist’s killing. No established link between the cases has been made at time of publication.
Trump said he hoped the series was "coincidence," but that White House officials would know more in the next week and a half. "Some of them were very important people, and we're going to look at it over the next short period," Trump told reporters on Thursday.
Obituaries and memorial posts are offering rare, concrete details about the missing and deceased scientists—and how abruptly their lives ended.
What To Know
A Daily Mail report on Thursday renewed attention on the 2022 death of Amy Eskridge, a 34-year-old scientist who reportedly died in Alabama of a self-inflicted gunshot wound after expressing concerns about her safety.
Another Mail report highlighted that Michael David Hicks, a longtime NASA Jet Propulsion Laboratory (JPL) scientist involved in asteroid and comet research, died in 2023 with no public cause of death disclosed,
The Mail reported that Hicks, 59, worked at JPL from 1998 to 2022 and contributed to more than 80 scientific papers, including roles on NASA’s Deep Space 1 mission and the DART asteroid‑deflection project, before his death on July 30, 2023; the report said his cause of death was not publicly disclosed and that it found no record of an autopsy.
Among the missing are retired Air Force Major General William Neil McCasland, last seen February 27 in Albuquerque, New Mexico, and aerospace engineer Monica Reza, who disappeared in June while hiking in California. Both have been cited by online sleuths as part of a pattern, though officials have not linked the cases.
Former FBI Assistant Director Chris Swecker told the Daily Mail recently “You can say these are all suspicious, and these are scientists who have worked in critical technology.”
Below is the list of workers with ties to advanced research whose disappearances or deaths since 2022 have been attracting public interest.
Michael David Hicks—Research scientist at NASA’s Jet Propulsion Laboratory; worked on the DART Project and Deep Space 1 mission.
Died: July 30, 2023.
Frank Maiwald—Principal researcher at NASA’s Jet Propulsion Laboratory.
Died: July 4, 2024.
Maiwald served as a principle investigator at the lab, managing high-profile Earth observation and space instrumentation efforts and earning several NASA honors for his work, Newsweek reported previously.
Anthony Chavez—Former employee at Los Alamos National Laboratory.
Missing since: May 8, 2025.
Chavez reportedly worked at the Los Alamos National Laboratory for decades before retiring in 2017. Police said at the time his family and friends considered the 78-year-old’s disappearance “out of character.”
Monica Reza—Director of materials processing at NASA’s Jet Propulsion Laboratory.
Missing since: June 22, 2025.
As previously reported by Newsweek, Reza worked on a government-funded rocket materials project that was overseen by McCasland. Police said she went missing while hiking in the Angeles National Forest in California.
Melissa Casias—Administrative worker at Los Alamos National Laboratory.
Missing since: June 26, 2025.
According to Fox News, Casias, 53, is an administrative employee with security clearance at the laboratory and was last seen walking along a New Mexico roadside. The outlet said family members have pushed back on the notion she left voluntarily.
Steven Garcia—Government contractor at the Kansas City National Security Campus' facility in Albuquerque, New Mexico.
Missing since: August 28, 2025.
According to reporting, Garcia was last seen leaving his Albuquerque home on foot and carrying a handgun. NewsNation said the 48-year-old worked as a property custodian at the Kansas City National Security Campus, which it noted manufactures over 80 percent of the non-nuclear components for U.S. nuclear weapons.
Nuno Loureiro—Director of MIT’s Plasma Science and Fusion Center.
Died: December 16, 2025 (after being shot on December 15, 2025).
Loureiro was a leading theoretical physicist whose work advanced understanding of plasma behavior in fusion reactors and astrophysical systems, according to an MIT obituary. He died after sustaining gunshot wounds.
The suspect in Loureiro’s killing was identified as Claudio Manuel Neves Valente, also the suspect in the Brown University mass shooting, who later died by suicide.
Carl Grillmair—Caltech astrophysicist who worked on NASA’s NEOWISE and NEO Surveyor missions.
Died: February 16, 2026.
The Caltech astrophysicist helped uncover dozens of stellar streams and contributed to major NASA missions including Spitzer, NEOWISE, and NEO Surveyor, according to a Caltech obituary. He died after being fatally shot at his California home.
William "Neil" McCasland—Retired U.S. Air Force major general.
Missing since: February 27, 2026.
As previously reported by Newsweek, McCasland held high-ranking roles in the U.S. Air Force spanning science, technology and space research, and was a commander of the Air Force Research Laboratory at Wright‑Patterson Air Force Base in Ohio.
Police said he was last seen near Quail Run Court NE in Albuquerque, and had left his phone, prescription glasses and wearable devices at home.
Some in UFO circles have speculated his disappearance may be connected in some way to his work, but his wife has pushed back against this.
Jason Thomas—Pharmaceutical researcher.
Found deceased: March 17, 2026.
A Legacy.com obituary published in April described Thomas—a 46‑year‑old pharmaceutical researcher at Novartis working on cancer treatments—as having "passed away unexpectedly after having been missing since December 12, 2025."
His body was recovered from Lake Quannapowitt in Wakefield, Massachusetts.
Amy Eskridge—Scientist
According to the Daily Mail, the scientist—who had been researching anti-gravity technology—died from a self-inflicted gunshot in 2022 after warning her life could be in danger.
She was the chair and president of the Institute for Exotic Science in Huntsville, which she co-founded, according to obituaries posted online. She said in a 2020 interview that she founded the institute “as a public-facing persona to disclose antigravity technology.”
Among the members of Congress that have spoken publicly about their concern surrounding the string of disappearances and deaths is Missouri Republican Representative Eric Burlison, who said recently he had requested the involvement of the FBI in the “deeply concerning” disappearances.
Burlison also previously suggested McCasland had “a lot of information” on the topic of UFOs. McCasland’s wife, meanwhile, has pushed back against speculation from the UFO community that his disappearance is related to classified information.
Representative Tim Burchett, a Tennessee Republican, told the Mail in March: “There have been several others throughout the country that have disappeared under suspicious circumstances. I think we ought to be paying attention to it.”
What Happens Next
Bernalillo County Sheriff’s Office, which has been investigating the disappearance of McCasland, told Newsweek on Wednesday there had been no new developments in the investigation, but that his case remained a top priority for the department.
Update, 4/14/26, 10:15 a.m. ET: This article was updated with additional information and a new headline.
Update, 4/22/26, 5:46 a.m. ET: This article has been updated with additional information.