Shooter Muhammad Youssuf Abdulazeez, 24, "was carrying tremendous firepower and ammunition," Robin Wyatt says she was told of the July 16 attack. "He had body armor. Anyone fighting him might as well have been using a bow and arrow."
Aware of the active shooter while keeping an open phone line to police, Wyatt and Gunnery Sgt. Thomas Sullivan rushed 18 others out of a building through a back door and over a high security fence. That's where a head count discovered that two people were missing.
"Marines never leave anyone behind," says Robin Wyatt.
"The survivors later said the gunfire was as hard as anything they heard in combat. A hail of fire was laid down. Wyatt and Sullivan went in against that to get to the two missing men.
"In the process, they gave their lives."
The naval training center's commander, Lt. Cmdr. Timothy White, fired his personal gun at Abdulazeez, and one of the slain Marines also may have returned fire with a personal weapon, reports the Air Force Times. But why the officers carried their own sidearms has become a point of controversy, since Defense Department policy prevents anyone other than military police or law enforcement from carrying weapons on federal property.
Marine Corps Maj. Clark Carpenter, while praising the "unquestionable bravery" of police "who certainly saved lives" by taking down the shooter, tells PEOPLE: "When everything comes out, this will be a story about valor."
"The fallen are part of a new legacy," he says. "All Marines should be proud of how this unit performed."
Sullivan, 40, of Hampden, Massachusetts, and known as "Gunny" to his friends, was an Iraq veteran and two-time Purple Heart recipient. A fellow Marine told his parents: "The only thing on his mind was if his Marines were okay."
Facebook(2); Russ Bynum / AP
Lance Cpl. Skip Wells, 21, of Cobb, Georgia, was shot after sending a final text to his girlfriend that read "ACTIVE SHOOTER." She thought he was joking, and after hearing nothing more from him as the gravity sank, Caroline Dove texted back, "I love you."
Petty Officer Randall Smith, 26, a Rossville, Georgia, father of three girls, who died two days after the attack from his injuries, "always wanted to do something bigger" than be an average Joe in school, a former teacher recalled. "He wanted to make a difference."
Wyatt, 35, of Burke County, North Carolina, has a daughter who will turn 10 on July 25, and he was an Eagle Scout who'd saved the life of an injured swimmer at age 16. His aunt recalls that he once woke her on a Montana campout to watch a geyser erupt in the moonlight.
"He had a wide-eyed sense of wonder for everything," says Robin Wyatt. "You don't always have to be a high-ranking officer to be a hero. Sometimes you can be Staff Sgt. David Wyatt."
Reporting by SUSAN KEATING
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