The explosion from an anti-personnel obstacle breaching system erupts here April 10 during Exercise Balikatan 2011. Marines from Combat Assault Battalion, 3rd Marine Division, III Marine Expeditionary Force, employed this weapon as part of the exercise. Balikatan 2011 is an annual bilateral training exercise between the Armed Forces of the Philippines and U.S. military to maintain operational readiness and strengthen the U.S.-Philippine relationship.