150815-N-AT895-235 CHATTANOOGA Tenn. (Aug. 15, 2015) Secretary of the Navy (SECNAV) Ray Mabus delivers remarks during a memorial service honoring the four Marines and one Sailor who were killed as a result of the shooting in the Navy Operational Support Center Chattanooga July 16. (U.S. Navy photo by Mass Communication Specialist 1st Class Nathan Laird/Released)