Saul Loeb / AFP - Getty Images

President Obama presents Rose Mary Sabo-Brown with a Medal of Honor for her late husband, Army Specialist Leslie H. Sabo, Jr., during a ceremony in the East Room of the White House.

President Barack Obama presented the country’s highest military decoration to the family of Army Spc. Leslie H. Sabo Jr., who was killed protecting fellow soldiers from an ambush in Cambodia during the Vietnam War.

The 22-year-old Army rifleman killed several North Vietnamese soldiers, shielded a comrade from a grenade blast and forced a retreat in a battle that took place on May 10, 1970.

The Medal of Honor was awarded to Sabo’s widow, Rose Mary Sabo-Brown,  in the East Room of the White House.

"He saved  his comrades who meant more to him than life," Obama said at the ceremony, while also saluting other Vietnam War veterans. Members of Sabo's unit, Bravo Company, were in attendance and received a standing ovation.

"A piece of metal won't bring back my husband," Sabo-Brown told the Pittsburgh Tribune-Review in an interview. "But my heart beams with pride for Leslie because he's finally getting what's due to him. I will show it proudly for him for the rest of my life."

Spc. 4 Leslie H. Sabo Jr. is shown during his tour with Company B, 3rd Battalion, 506th Infantry, 101st Airborne Division. He will receive the Medal of Honor May 16 for his valor in Vietnam.

The records of the Pennsylvania man's heroics were lost in military archives for decades before being re-discovered in 1999 by a magazine writer researching Vietnam era Medal of Honor recipients.

Related: Soldier to receive posthumous Medal of Honor for heroic actions in 1970 Cambodia battle

Sabo’s platoon was on patrol in the Se San River valley in Cambodia when they were ambushed by a larger North Vietnamese force.

Sabo quickly charged and killed several enemy soldiers. Then, according to the White House, Sabo rushed at another oncoming flanking force and drew fire away from American troops, forcing the North Vietnamese to retreat.

As Sabo was reloading his rifle, a grenade landed nearby. He picked it up, threw it and shielded a fellow soldier with his own body. Wounded from the blast and enemy fire, he continued to fight, storming an enemy emplacement and throwing another grenade. The grenade explosion silenced the enemy, but also killed Sabo, the White House said.

Sabo’s remains were shipped home in a body bag marked “Remains Unfit for Viewing,” his hometown newspaper, the Ellwood City Ledger, reported. His father and namesake died in 1977 without knowing the full story of his son’s death.

A citation recommending Sabo for the Medal of Honor was lost after the war, but resurfaced in 1999 when Alton “Tony” Mabb, a writer for a military association magazine, was researching Vietnam-era Medal of Honor recipients at the National Archives.

Mabb contacted Sabo's widow and met with her and other members of his platoon at the Vietnam Veteran's War Memorial in Washington, D.C., in 2002, according to an account in the Pittsburgh Post-Gazette. Mabb also contacted U.S. Rep. Corrine Brown, who wrote the Defense Department requesting that Sabo's actions be recognized. In 2006, Sabo was recommended for the Medal of Honor by the Secretary of the Army.

It took an act of Congress to extend the time limit for the medal, which was passed in the 2008 defense authorization act.

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