A nuclear physicist and MIT professor shot dead outside his Massachusetts home. A retired Air Force general missing from his residence in New Mexico. An aerospace engineer vanished during a hike in Los Angeles.
They are among at least 10 individuals tied to sensitive US nuclear and aerospace research who have died or disappeared in recent years, according to a CNN report.
The cases are now under federal scanner, raising questions about possible links, and fueling online speculation about foul play.
The Federal Bureau of Investigation (FBI) says it “is spearheading the effort to look for connections into the missing and deceased scientists,” adding that it “is working with the Department of Energy, Department of War, and with our state … and local law enforcement partners to find answers.”
Separately, the Republican-led House Oversight Committee announced Monday it will investigate reports surrounding the deaths and disappearances of these individuals, noting they had access to highly sensitive scientific information, the report mentioned.
The reports “raise questions about a possible sinister connection” between the deaths and disappearances, the committee said, requesting briefings from the FBI, the Defence Department, the Department of Energy and National Aeronautics and Space Administration (NASA), independent US government space agency.
The Defence Department said only that it would respond directly to the committee, while the Department of Energy referred inquiries to the White House.
In a post on X, NASA said it is “coordinating and cooperating with the relevant agencies” in relation to the scientists.
“At this time, nothing related to NASA indicates a national security threat,” NASA spokesperson Bethany Stevens said.
The mystery cases
The mysterious cases themselves vary widely. Some involve unsolved homicides; others are missing persons cases with no clear signs of foul play. In at least two instances, families have cited preexisting medical conditions or personal struggles, per the CNN report.
Authorities have not established any confirmed links between the cases.
The White House reportedly said last week it is also working with federal agencies to examine any possible connections, with President Donald Trump calling the situation “pretty serious stuff.”
“It’s very unlikely that this is a coincidence,” House Oversight Chair James Comer, a Republican, told ‘Fox News Sunday.’
“Congress is very concerned about this. Our committee is making this one of our priorities now because we view this as a national security threat.”
Rep. James Walkinshaw, a Democrat on the Oversight Committee, agreed an investigation is warranted but cautioned against assuming coordination.
“The United States has thousands of nuclear scientists and nuclear experts,” Walkinshaw told CNN’s Erin Burnett on Tuesday. “It’s not the kind of nuclear programme that potentially a foreign adversary could significantly impact by targeting 10 individuals.”
‘It’s getting serious’
Lawmakers trace the timeline back to 2023, beginning with the death of Michael David Hicks, a longtime NASA Jet Propulsion Laboratory scientist.
Hicks, 59, died July 30, 2023. Over nearly 25 years at JPL, he specialised in comets and asteroids, according to the American Astronomical Society. His cause of death was not disclosed.
His daughter, Julia Hicks, told CNN her father had been dealing with known medical issues and said the recent speculation has left her uneasy.
“From what I know of my dad, there’s no train of logic to follow that would implicate him in this potential federal investigation… I don’t understand the connection between my dad’s death and the other missing scientists,” she was quoted as saying.
“I can’t help but laugh about it, but at the same time, it’s getting serious,” Hicks said.
She added that as of Tuesday afternoon, no one from government or federal agencies had contacted her about her father’s death.
More mystery deaths, missing cases
In the years since, others connected to JPL have also died or gone missing. Frank Maiwald, a space research specialist, died in Los Angeles in 2024 at age 61. Monica Reza, a 60-year-old aerospace engineer, disappeared while hiking in a Los Angeles forest in June 2025. She had served as director of the lab’s Materials Processing Group, according to the House Oversight Committee.
Also missing is William Neil McCasland, a retired Air Force major general who has not been seen since February 27, when he left his home in Albuquerque, New Mexico, without his phone, glasses or wearable devices. The FBI is now assisting in the search.
McCasland had overseen some of the Pentagon’s most advanced aerospace programs and previously commanded the Air Force Research Laboratory at Wright-Patterson Air Force Base. Months after his disappearance, officials still cannot determine where he went, why he left, or whether anyone else was involved.
