(CNN) He died saving the lives of others, and now he's receiving posthumous medals for his heroic actions.

Authorities said the ROTC cadet was shot and killed along with fellow student Reed Parlier, 19. Four others were injured in last month's mass shooting. Trystan Terrell , 22, has been indicted on two counts of murder and four counts of attempted murder.

During Wednesday's ceremony, Vietnam War veteran Thomas "Stormy" Matteo praised Howell's actions in a FaceTime call to the late 21-year-old's parents and siblings.

The Howell family received a plaque that described the student's actions: "It is with great Honor and Respect to present the American Hero Award posthumously to Riley C. Howell. Cadet Howell with complete disregard for his personal safety, made a decision to stop an Active Shooter on his college campus."

Howell charged the shooter after he opened fire with a pistol in a classroom, tackling "the suspect to the ground covering his body, in the attempt to stop the attack," the plaque reads.

Matteo, president of the Purple Heart Society, is the recipient of six Purple Heart medals for action with the Marines in Vietnam.

Howell was remembered earlier this month at a memorial service with military honors.

"Maybe it was God that moved the levers, that put Riley in that classroom on that day, at the exact time for the purpose of saving others," said Kevin Westmoreland, the father of Howell's girlfriend, Lauren.

"It was not out of character for him," he said, "and maybe someone in that room is here for a greater purpose, and it was Riley's destiny to sacrifice himself for them."

According to an obituary for the student, Howell "was an adventurous guy who loved the outdoors, whether that was kayaking through inlets on the ocean, canoeing down cold mountain rivers, or screaming with excitement as he tried to do a front flip off the rope swing at Fontana Lake."