The US government has been left alarmed by reports that nearly a dozen US scientists have been dead or missing since 2023 in mysterious circumstances.
US President Donald Trump earlier this week said that his administration is examining the issue and will release information soon.
“I hope it’s random, but we’re going to know in the next week and a half,” Trump said. “Pretty serious stuff … hopefully a coincidence, or whatever you want to call it.”
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The White House says it is looking into the reports and will get answers soon.
“I haven’t spoken to our relevant agencies about it. I will certainly do that, and we’ll get you an answer,” White House press secretary Karoline Leavitt said. “If true, of course, that’s definitely something I think this government and its administration would deem worth looking into.”
There are reports that the scientists who have died or gone missing in suspicious circumstances worked on nuclear energy or on unidentified aerial phenomena (UAPs), formerly known as UFOs. Interestingly, four of these individuals are from New Mexico.
But what do we know? Who are the scientists missing? What’s going on?
Let’s take a closer look.
The missing
William Neil McCasland
The most recent person to go missing is
Major General William Neil McCasland. According to Fox News Digital, McCasland disappeared in February. He worked in space research and acquisition at the Pentagon.
McCasland left his phone, prescription glasses and wearable devices at home. However, he took hiking boots, and his wallet and a .38-calibre revolver were missing. McCasland also headed up the Phillips Research Site of the Air Force Research Laboratory at Kirtland Air Force Base in New Mexico, as well as the Air Force Research Laboratory at Wright-Patterson Air Force Base in Ohio. The latter facility has long been a bane of UFO conspiracy theorists, who claim it is tied to the 1947 Roswell crash.
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Interestingly, McCasland’s name turned up in the 2016 hacks of Hillary Clinton campaign chairman John Podesta by WikiLeaks. The messages claimed that McCasland worked on UAPs. McCasland’s wife, Susan Wilkerson, took to social media in the aftermath of his disappearance to dismiss any links to the Roswell crash.
Official portrait of United States Air Force Major General William N McCasland. Image courtesy: US Air Force
“Neil does not have any special knowledge about the ET bodies and debris from the Roswell crash stored at Wright-Patt,” Wilkerson wrote. Adding that he retired in 2013, she said, “It seems quite unlikely that he was taken to extract very dated secrets from him.”
NBC News quoted Wilkerson
telling the police that she believed he did not wish to be found.
Monica Reza
Monica Reza, director of materials processing at Nasa’s Jet Propulsion Laboratory, went missing in June last year.
According to The Times of India, a Crescenta Valley Sheriff’s Office alert said Reza was witnessed hiking along Angeles Crest Highway at 9:10 am on June 22, 2025. Reza was hiking alongside a friend who said he was 30 feet ahead of her when she disappeared.
STORY CONTINUES BELOW THIS ADMonica Reza, director of materials processing at Nasa’s Jet Propulsion Laboratory, went missing in June last year. Image courtesy: Facebook
It also noted that the Sheriff’s Homicide Bureau was investigating the matter.
The New York Post, calling Reza a rocket scientist, noted the “close professional connection” between her and McCasland and the fact that they disappeared within eight months of each other.
Steven Garcia
According to Times Now, Steven Garcia, a government contractor at the Kansas City National Security Campus in Albuquerque, went missing in August.
Steven Garcia was last seen in Albuquerque, New Mexico. Image courtesy: missingpersons.dps.nm.gov
KOB4 quoted multiple reports as saying that the campus manages non-nuclear components of nuclear weapons. Garcia. 47, was reportedly a property custodian who would have kept an eye on these components and had a certain level of security clearance.
Anthony Chavez
Anthony Chavez,
who previously worked at Los Alamos National Laboratory (LANL), disappeared under mysterious circumstances. The 78-year-old was last seen at his Los Alamos home in May 2025.
Anthony Chavez of Los Alamos went missing in May 2025. Los Alamos County Police Department/Facebook
According to the Daily Mail, “Chavez left his car locked in the driveway and did not take his wallet, keys or other personal items, which were all found inside Chavez’s home.” The Los Alamos Police Department called on the public to help them find him.
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Melissa Casias
According to KOB4, Casias was an administrative assistant at LANL. She went missing in June 2025. According to Live Now Fox, Casias was last seen walking on the side of a road in Taos County, New Mexico.
Melissa Casias was last seen dropping off her daughter’s lunch at work. Image courtesy: Dateline NBC/Facebook
Her niece said the 53-year-old had picked up a sandwich and dropped it off for her daughter earlier in the day. Casias’ family found her car, purse, keys, and her personal and work-related phones at her home. However, the phones had been wiped clean via a factory reset. They denied any notion that Casias would have disappeared willingly, saying she was preparing to care for their mother, who had an impending surgery.
The dead
Frank Maiwald
Frank Maiwald, a scientist, died in July 2024. According to Live Now Fox, Maiwald also worked at Nasa’s JPL. No public cause of death was given for the long-time engineer, and the obituary online was brief. No autopsy is believed to have been performed.
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Maiwald, during his time at JPL, worked on building instruments that could trace chemical signatures, including water and organic molecules, that researchers could use to evaluate whether it is possible for life to exist outside Earth.
Michael David Hicks
Michael David Hicks, another
NASA Jet Propulsion Laboratory research scientist, died in July 2023.
Michael David Hicks of Sunland, CA passed away on July 30, 2023, at 59 years of age. Image courtesy: lpl.arizona.edu
According to Times Now, Hicks worked on the DART asteroid defence project and published over 80 scientific papers. Hicks worked at JPL from 1998 to 2022. Like Maiwald, there was no cause of death given.
Jason Thomas
According to The Times of India, Jason Thomas was a pharma researcher at Novartis. Thomas initially went missing in December 2025.
Jason Thomas worked at Novartis. Image courtesy: LinkedIn
Then, his body was found in Lake Quannapowitt in Wakefield in March 2026. People have said Thomas was struggling with the deaths of his parents. According to the police, no foul play is suspected.
Nuno Loureiro
According to Live Fox Now, Nuno Loureiro died after being shot at his home in Brookline, Massachusetts, in December 2025. The 47-year-old was an MIT professor of nuclear science and engineering and physics. Police have said he was shot by Claudio Manuel Neves Valente, an individual known to him from university in Portugal.
STORY CONTINUES BELOW THIS ADNuno Loureiro was an MIT professor of nuclear science and engineering and physics. Image courtesy: physics.mit.edu
Loureiro was said to be a pioneering figure in fusion energy research. He was studying plasma physics and working on technologies that aimed to produce near-limitless clean energy. Authorities have thus far drawn no link between Loureiro’s work and his death.
Carl Grillmair
According to The Times of India, Carl Grillmair was shot dead on the front porch of his home around 6 am in February. The 67-year-old California Institute of Technology astrophysicist’s work was linked to Nasa’s JPL as well as missile tracking technology used by the Air Force.
Carl Grillmair was shot dead on the front porch of his home around 6 am in February. Image courtesy: ipac.caltech.edu
According to Fox Now Live, Grillmair worked on many of Nasa’s initiatives, including the Hubble and Spitzer space telescopes, as well as galactic structure, dark matter and the search for habitable planets.
Authorities later arrested a 29-year-old suspect in connection with Grillmair’s killing, charging him with murder as well as carjacking and burglary in separate incidents.
‘Don’t think it shows evidence for a plan’
Though some are eager to point out certain links between dead and missing scientists, others are equally vociferous about dismissing any notion of a planned conspiracy or any ties to nuclear secrets or work on UFOs.
“The common denominator of the practising scientists is not great, and I would caution against assigning too much significance to that,” Avi Loeb, a physicist and professor at Harvard University, told FOX 32’s Chicago Report. “Of course, each of these cases is a mystery that has to be resolved. It’s possible there was someone aiming to harm those individuals. But I don’t think it shows any evidence of a plan just because these people, for example, worked on unidentified anomalous phenomena (UAP) … I would not be too concerned with this being coordinated.”
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Barry Roth, Chief Archivist of the National UFO Historical Records Center in Rio Rancho, told the outlet KOB4, “But you have one person involved who has alleged ties to the UFO/UAP community, and then all of a sudden people might find other patterns that might tie the other people in. When you do a deep dive into it, there isn’t really any other connection,” he said.
He said the link between four cases in New Mexico is likely only “geography”.
“If there’s no pattern that initially exists, they’ll find a pattern that exists that points to that specific topic of interest they’re looking at, and they’ll start making tie-ins. You can take pretty much any subject and create a pattern for it if you look hard enough,” Roth said. He said it was possible that they were having mental health issues.
“You know, people who are under that kind of pressure in whatever field they’re in, whether it’s defence or nuclear or propulsion, you’ve got to pay attention to their mental health, too.”
FAQs
1. How many US scientists have been reported dead or missing since 2023?
At least 10 US scientists have been reported dead or missing under mysterious circumstances since 2023.
2. Is there evidence linking these cases to a conspiracy or national security issues?
Thus far, there is no concrete evidence of a coordinated conspiracy or links to nuclear secrets or UFO-related work.
3. What explanations have experts offered?
Experts have said the cases are likely unrelated and that they may be a coincidence, and that the individuals involved may have suffered physical or mental health issues.
With inputs from agencies
First Published:
April 17, 2026, 14:38 IST
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