White House Probes Disappearances, Deaths of US Scientists with Classified Access

Several government employees with high-level security clearances have gone missing or died under mysterious circumstances.

Apr. 16, 2026 at 9:39pm

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A photorealistic painting of a nondescript government research facility, its windows glowing with warm light against a backdrop of deep shadows, evoking a sense of unease and mystery surrounding the recent disappearances of scientists with high-level security clearances.The disappearances of government scientists with access to classified information have sparked an investigation into potential national security threats.Kirtland Today

The White House says it will investigate the disappearances and deaths of several U.S. government scientists and employees who had access to highly classified nuclear and space information. The cases have drawn attention because of the victims' access to top secret data, though law enforcement and other experts don't see a clear connection between the incidents.

Why it matters

The disappearances and deaths of these government scientists and researchers with access to sensitive national security information have raised concerns about potential security breaches or foul play. The White House is now looking into the cases to determine if there is any coordinated effort targeting individuals with classified knowledge.

The details

Over the past two years, several U.S. government scientists and employees with high-level security clearances have gone missing or died under mysterious circumstances. The cases include retired Air Force Maj. Gen. Neil McCasland, aerospace engineer Monica Jacinton Reza, government contractor Steven Garcia, astrophysicist Carl Grillmair, MIT physicist Nuno Loureiro, NASA engineer Frank Maiwald, and Los Alamos National Lab employees Melissa Casias and Anthony Chavez. While the victims' access to classified nuclear, space and defense information has drawn attention, law enforcement and other experts say they don't see a clear link between the incidents.

  • On February 27, 2026, retired Air Force Maj. Gen. Neil McCasland disappeared in Albuquerque, New Mexico.
  • On June 22, 2025, aerospace engineer Monica Jacinton Reza went missing while hiking in the Angeles National Forest.
  • On August 28, 2025, government contractor Steven Garcia disappeared after leaving his home in Albuquerque.
  • On February 16, 2026, astrophysicist Carl Grillmair was shot and killed outside his California home.
  • In December 2025, MIT physicist Nuno Loureiro was shot at his home in Brookline, Massachusetts and later died.

The players

Neil McCasland

Retired Air Force Maj. Gen. Neil McCasland held senior roles at the Pentagon and in space research and acquisition. He commanded the Phillips Research Site of the Air Force Research Laboratory and the Air Force Research Laboratory.

Monica Jacinton Reza

A 60-year-old aerospace engineer and co-creator of a nickel-based alloy for rocket engines, Reza was the Director of Materials Processing at NASA's Jet Propulsion Laboratory.

Steven Garcia

A 48-year-old government contractor with ties to the Kansas City National Security Campus, which produces non-nuclear components for the U.S. nuclear weapons arsenal.

Carl Grillmair

A 67-year-old California Institute of Technology astrophysicist known for his work on exoplanets and the discovery of water on distant worlds.

Nuno Loureiro

A 47-year-old MIT physicist and director of the university's Plasma Science and Fusion Center, Loureiro was a leading figure in fusion energy research.

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What they’re saying

“I hope it's random, but we're going to know in the next week and a half. I just left a meeting on that subject. Pretty serious stuff.”

— Donald Trump, President of the United States

“The common denominator of the practicing scientists is not great, and I would caution of assigning too much significance to those. 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 some evidence for a plan, just because, these people, for example, worked on unidentified anomalous phenomenon (UAP) … I would not be too concerned with this being coordinated.”

— Avi Loeb, Physicist and Professor, Harvard University

What’s next

The White House says it will provide an update on its investigation into the disappearances and deaths of the government scientists and employees within the next week and a half.

The takeaway

The mysterious disappearances and deaths of these government scientists and researchers with access to highly classified information have raised serious national security concerns, prompting the White House to launch a full investigation to determine if there is any coordinated effort targeting individuals with sensitive knowledge.