On the night of March 24, 2014, Master-at-Arms 2nd Class Mark Aaron Mayo, 24, was fatally shot while defending a fellow sailor aboard USS Mahan at Naval Station Norfolk. A civilian truck driver, identified as 35-year-old Jeffrey Tyrone Savage, gained unauthorized access to the base, left his truck at Pier 1, and boarded the ship. Savage confronted the Petty Officer of the Watch on the quarterdeck, disarmed her and prepared to shoot. Mayo, serving as Chief of the Guard, rushed in from the pier and placed himself between Savage and the unarmed officer; Mayo was shot and killed. Responding Navy Security Forces returned fire and killed Savage at the scene.

A subsequent investigation found significant security lapses at the naval station and disciplinary action was taken against six individuals, including the commanding officer of Naval Station Norfolk. Savage was reported to have a prior voluntary manslaughter conviction and to have been under the influence of synthetic marijuana; acquaintances described him as a loner with financial stress and delusions. Mayo was posthumously awarded the Navy and Marine Corps Medal and was buried at Arlington National Cemetery.