160504-N-TC720-050 ROTA, Spain (May 4, 2016) Sailors aboard USS Donald Cook (DDG 75) respond to a mass casualty drill May 4, 2016. Donald Cook, an Arleigh Burke-class guided-missile destroyer, forward deployed to Rota, Spain is conducting a routine patrol in the U.S. 6th Fleet area of operations in support of U.S. national security interests in Europe. (U.S. Navy photo by Mass Communication Specialist 2nd Class Mat Murch/Released)