Chief Warrant Officer 2 Lucas Sheehan, a counter intelligence and human intelligence officer with Special Purpose Marine Air-Ground Task Force - Southern Command breaks the seal of an M50 gas mask with his fingers during gas chamber training at Marine Corps Base Camp Lejeune, North Carolina, March 16, 2020. Training for chemical, biological, radiological, nuclear defense defense is an event in which Marines and Sailors are exposed to CS gas in order to familiarize themselves with the use of a gas mask. Marines and Sailors with SPMAGTF-SC are conducting a variety of pre-deployment training events and qualifications in order to enhance crisis response preparedness in and around Latin America and the Caribbean. These events assist the Marines and Sailors with providing security cooperation training and engineering projects alongside partner nation military forces in Central and South America. Sheehan is a native of Murrysville, Pennsylvania. (U.S. Marine Corps photo by Sgt. Andy O. Martinez)