I didn’t know this was a thing until today...
The Foreign Emergency Support Team (FEST) is the U.S. governments only interagency, on-call, short-notice team poised to respond to terrorist incidents worldwide. The FEST deploys to assist and advise the U.S. Chief of Mission in assessing crises and coordinating U.S. government crisis response activities. The FEST includes representatives from the US Department of State, Department of Defense, the Intelligence Community, and the Federal Bureau of Investigation, and other appropriate agencies, such as the Department of Energy, as circumstances warrant. FEST composition is flexible and tailored to the specific incident and U.S. Embassy needs. The FEST provides specialized crisis response expertise to augment existing U.S. Mission and host government capabilities
” . . . such as the Department of Energy”
This sounds like a suped-up version of the NEST: Nuclear Emergency Support Team.
Burying the lede a little.