CBS’ '60 Minutes' reports on unexplained brain trauma suffered by U.S. diplomats in Cuba and China. According to the segment, 25 Americans in Cuba suffered serious brain injuries in 2016 and 2017 and at least 15 American officials in China also experienced unexplained brain trauma soon after. The FBI is currently investigating if this was caused by a hostile foreign government attack with a mysterious weapon.

Correspondent Scott Pelley interviews multiple sources who have been suffering from symptoms including Mark Lenzi, a State Department security officer, who worked in China.

Teena Shetty, MD, neurologist at HSS, recalls that while Lenzi did not have any history of trauma, he reported a number of neurologic symptoms characteristic of mild traumatic brain injury.

"The presumption is that something happened which caused a functional brain injury of widespread brain networks because he has symptoms to reflect a multitude of brain networks," explains Dr. Shetty.

Watch the full segment at CBSNews.com. This also aired on March 17, 2019.