I'm Gianno Jalosi with your Fox True Crime Minute.

A missing scientist has been found dead in New Mexico once again under mysterious circumstances.

53-year-old Melissa Casillas had been missing since June 26th of last year.

She was working as an administrative assistant at Los Alamos National Lab,

where the world's first atomic weapons were developed during World War II.

Investigators announcing her remains were found by a

hiker in a national forest about 10 miles from her northern New Mexico home in an area that had been

searched before. A handgun was also found alongside her body. When Casillas vanished, her personal

belongings, including her purse, IDs, and cell phones had been left behind, and both phones had

reportedly been factory reset. Casillas is one of at least

10 people with high-level access to sensitive U.S. nuclear and aerospace research who've either

disappeared or died under murky circumstances in recent years, at least three of whom still

remain missing to this day. State police say an extensive investigation into what happened to

Casillas remains active. There's more on this story at Fox News.com or subscribe to the Fox True Crime podcast.

I'm Gianna Jalosi with your Fox True Crime Minute.