FBI investigating recent deaths and disappearances of multiple US scientists

Some of the scientists worked for NASA. (Reuters: NASA/Kim Shiflett) Link copiedShareShare articleOn a gloomy morning in Los Angeles, Monica Reza and a friend from yoga class set out on a hike in the San Gabriel Mountains. Midway through the hike on June 22, 2025, Monica fell about 30 metres behind her companion. Her friend glanced back to see Monica smiling and waving to say she was OK. Monica Reza went missing while hiking in the California region. (Supplied) But when her hiking partner looked back again moments later, Monica was gone. Search and rescue teams searched for days for her body, but all they found was Monica's beanie. The director of materials processing at NASA's Jet Propulsion Laboratory joined a growing list of US scientists who had recently gone missing or died. That list is made up of at least 12 US scientists who supposedly all had access to sensitive government research. Some worked for NASA, others studied nuclear science and astrophysics, and some worked on UFO research. The nature of their work has led to speculation and conspiracy theories that they might all be connected. It sounds like the plot of a blockbuster spy movie and is "pretty serious stuff," according to US President Donald Trump. "Coincidence, whatever you want to call it … but some of them were very important people, and we're going to look at it over the next short period," Mr Trump said in April. FBI director Kash Patel confirms an investigation is ongoing, while Donald Trump says the matter is "serious". (Reuters: Jonathan Ernst) The US Committee on Oversight and Government Reform said in a letter to the FBI that the incidents were a "grave threat" to the country. "These deaths and disappearances may represent a grave threat to US national security and to US personnel with access to scientific secrets," the letter said. Both the US Congress and the FBI have launched investigations into the deaths and disappearances. FBI director Kash Patel said "we're going to look for connections" and noted the FBI would take a closer look at "foreign actors". "If there's any connection that leads to nefarious conduct or conspiracy, the FBI will make the appropriate arrest," he said. South Carolina congresswoman Nancy Mace posed the question many on the internet were asking. According to public reports and a statement from the House Oversight Committee, the first death to cause concern was that of Michael David Hicks in July 2023. And the most recent incident the committee believe could be linked is the disappearance of retired US Air Force major general William McCasland on February 27 this year. Concerns of a "sinister connection between a string of mysterious deaths and disappearances" were raised by the Oversight Committee on April 20. Not all of the people who have been linked were scientists. Some worked as security officers or admin workers at top-secret government facilities. Here is the list in order of their death or disappearance: Died on July 30, 2023. No official cause of death has been given. Worked as a scientist at the NASA Jet Propulsion Laboratory (JPL) from 1998 to 2022. His speciality study area was the physical properties of comets and asteroids. Hicks worked on the DART planetary defence project, the Near Earth Asteroid Tracking (NEAT) Project, the Dawn Mission, and the NASA Deep Space 1 Mission. Died on May 12, 2024, from an accidental drug overdose. He was a former air force intelligence officer and a Bronze Star recipient for his service in Afghanistan. Sullivan was part of the US government’s UFO crash retrieval program, sources told the New York Post. According to those sources, he had seen UFOs and was due to testify about his eye-witness accounts at a congressional hearing in November 2024. Died on July 7, 2024. No official cause of death has been given. Maiwald worked as an imaging spectroscopy engineer at NASA's Jet Propulsion Laboratory. He was the principal investigator on Earth-observing and space instrumentation projects. Chavez is a former Los Alamos National Laboratory employee. He worked as a construction foreman at the site. Los Alamos was the site of the US government's top-secret Manhattan Project during World War II. A detective investigating his disappearance said there were no indications of foul play, but also no signs that he was planning to leave. Carl Buckland, a close friend of Chavez, said "his disappearance is extremely unusual" in a Facebook post. Reza was a metallurgist and materials engineer at NASA's Jet Propulsion Laboratory. She was the director of the Materials Processing Group at the NASA lab, and she co-invented a nickel-based superalloy used in rocket engines. The 60-year-old was last seen going for a hike in the Angeles National Forest. Casias was an admin assistant at NASA's Los Alamos National Laboratory. She was last seen by her husband after she dropped him off at work in the morning, before she was due to head home. Her d

FBI investigating recent deaths and disappearances of multiple US scientists

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