Navy sailors investigate for gas leaks during a toxic gas drill on the Arleigh Burke-class guided-missile destroyer USS Oscar Austin in the Atlantic Ocean, Oct. 14, 2017. The Oscar Austin is on a routine deployment supporting U.S. national security interests in Europe and increasing theater security cooperation and forward naval presence in the U.S. 6th Fleet area of operations. Navy photo by Petty Officer 2nd Class Ryan Utah Kledzik