Marines with Combat Logistics Battalion 31 and Battalion Landing Team, 3rd Battalion, 5th Marines, hold security after a simulated improvised explosive device detonation during humanitarian assistance-disaster relief training as part of Certification Exercise at Freshwater Beach, Shoalwater Bay Training Area, Queensland, Australia, Aug. 17, 2017. During CERTEX, Marines with CLB-31, the Logistics Combat Element for the 31st Marine Expeditionary Unit, and Marines with BLT 3/5, the Ground Combat Element for the 31st MEU, refined their abilities to provide security and life-sustaining support for possible HADR operations. The 31st MEU and Amphibious Squadron 11 are conducting CERTEX, the final evaluation in a series of training exercises which ensures readiness for crisis response throughout the Indo-Asia-Pacific region. The 31st MEU partners with PHIBRON 11 to form the amphibious component of the Bonhomme Richard Expeditionary Strike Group. (U.S. Marine Corps photo by Cpl. Amaia Unanue/Released)