In an interview with Fox News Sunday, he said there’s a formal probe within the Department of Energy that’s part of a coordinated investigation across various branches of the government.

“A lot of the nuclear security scientists are in DOE,” he added. “So yes, of course we are looking into this.”

When asked if the inquiry has turned up anything, Wright replied, “Too early to say about that. We haven’t found anything alarming yet.” 

The disclosure of the investigation comes after President Donald Trump was asked about the scientists on Thursday.

“I hope it’s random, but we’re going to know in the next week and a half,” he told reporters Thursday on the South Lawn of the White House, noting he had just attended a meeting on that subject.

“Hopefully, I don’t know, coincidence—whatever you wanna call it—but some of them were very important people, and we’re going to look at it,” he added.

The trend began a few years ago, and alarm bells grew louder after retired Air Force Maj. Gen. William McCasland went missing from his New Mexico home in February. He was previously the commander of the Air Force Research Laboratory on Wright-Patterson Air Force Base.

Others who have disappeared include aerospace engineer Monica Jacinto Reza; administrative assistant Melissa Casias, who had a security clearance at Los Alamos National Laboratory; Anthony Chavez, a retired Los Alamos worker; and Steven Garcia, a property custodian for the National Nuclear Security Administration.

Los Alamos National Laboratory and the National Nuclear Security Administration are part of the Department of Energy, which is involved in the development and maintenance of the U.S. nuclear arsenal, among other things.

Meanwhile, MIT physicist Nuno Loureiro and Caltech astrophysicist Carl Grillmair were killed, while Novartis scientist Jason Thomas and NASA Jet Propulsion Lab engineer Frank Maiwald have been found dead.

Rep. Eric Burlison, R-Mo., pointed out that several of the people left their homes without their phones.

“They just literally disappeared, left all of their devices at home,” he told Fox News. “This is not normal.”