'Grave threat': 3 things to know about investigations into missing US scientists

2. 'Grave threat' to US national security, lawmakers warn

House Committee on Oversight and Government Reform Chairman, Rep. James Comer, R-Ky., and Subcommittee on Economic Growth, Energy Policy, and Regulatory Affairs Chairman, Rep.  Eric Burlison, R-Mo., are seeking answers through an investigation into the missing and deceased scientists. 

On April 20, the pair sent letters to Department of Energy Secretary Chris Wright, Department of War Secretary Pete Hegseth, FBI Director Kash Patel and NASA Administrator Jared Isaacman. 

The letters cited reports that at least 10 individuals who “had a connection to U.S. nuclear secrets or rocket technology,” have “died or mysteriously vanished in recent years.” As Comer and Burlison noted, if the reports are accurate, “these deaths and disappearances may represent a grave threat to U.S. national security and to U.S. personnel with access to scientific secrets.”

“Specifically, public reports raise questions about a possible sinister connection between a string of mysterious deaths and disappearances which began in 2023 with the death of Michael David Hicks, who worked as a scientist at the NASA Jet Propulsion Laboratory (JPL) from 1998 to 2022,” the letters explained.

“Another JPL alum, Monica Reza, who served as the director of the NASA Lab’s Materials Processing Group, disappeared while hiking in California in June 2025 and remains missing,” the documents continued. 

The committee chairmen requested a state-level briefing from the agencies on the topic no later than Monday.