The disappearances and deaths of nearly a dozen scientists with ties to secretive U.S. scientific information have raised alarms about national security, prompting a House Oversight Committee investigation.

The string of deaths and disappearances began with the death of Michael David Hicks, who worked as a scientist at the NASA Jet Propulsion Laboratory from 1998 to 2022, according to the Committee on Oversight and Government Reform. At least 10 individuals so far who “had a connection to U.S. nuclear secrets or rocket technology” have gone missing or died in recent years.

The Trump administration has said the FBI and other federal agencies are also looking into the mysterious disappearances, with press secretary Karoline Leavitt saying they will “review all of the cases together and identify any potential commonalities that may exist.”

Here are three things to know about the disappearances and deaths of scientists connected to U.S. nuclear secrets and other sensitive scientific information.

1. Speculation That China, Russia or Iran is Involved

Following the launch of a House Oversight Committee investigation into the disappearances, Rep. Eric Burlison, R-Mo., believes that the country’s adversaries could be connected to the scientists’ disappearances and deaths.

“I would not be surprised if our adversaries, China, Russia, Iran or any other adversary saw an opportunity to take out some of our nation’s top scientists,” Burlison told News Nation, adding that he is “worried for the rest of our nation’s scientists.”

“These scientists are not hardened. They don’t have a security detail. So they would be a very easy target,” Burlison said.

In a statement this week to News Nation, the FBI confirmed that it’s “spearheading the effort to look for connections into the missing and deceased scientists.”

“We are working with the Department of Energy, Department of War, and with our state and local law enforcement partners to find answers,” the FBI said.

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.

3. Missing or Deceased Scientists Connected to US Nuclear Secrets

The committee’s letters referenced “unconfirmed public reporting” on the disappearance and death of individuals, noting that they had “access to sensitive U.S. scientific information.”

Among the individuals who disappeared within the last several years is Air Force Maj. Gen. William Neil McCasland, who went missing from his home in Albuquerque, New Mexico, in February. McCasland is believed to have left home with a .38 caliber revolver at the time of his disappearance.

He had been involved in aerospace research throughout his career, but had been retired for at least 13 years, according to a Facebook post by his wife in March.

McCasland allegedly had a “close professional connection” with Monica Reza, who served as the director of the NASA Lab’s Materials Processing Group, the congressional committee noted. The two were connected through an Air Force-funded research program in the early 2000s on “advanced materials needed for reusable space vehicles and weapons.”

Reza also disappeared while hiking in California in June 2025, according to reports. In addition to scientists associated with NASA JPL, the other missing or deceased individuals include people affiliated with the Los Alamos National Laboratory and an MIT scientist working on nuclear fusion.

All of the missing or deceased individuals appear to have had some sort of connection to U.S. nuclear secrets or rocket technology, which has prompted concerns about a possible national security threat.

Article written by Samantha Kamman and originally appeared on The Christian Post.