Search for missing nuclear scientists

The FBI has announced it will lead an effort to determine if there are any connections between the seemingly unrelated cases, which have fueled national security concerns.

President Donald Trump has called the situation 'serious stuff' and recently attended a high-level briefing on the matter.

Some members of Congress have suggested the string of incidents could be part of a coordinated foreign operation targeting American technological expertise.

NASA and other federal agencies are reportedly cooperating with the probe as the number of missing personnel continues to rise.