President Obama awarded the Medal of Honor for conspicuous gallantry to 24 Army veterans, delivering an emotional tribute to the men Tuesday before a room filled with family, friends and military leaders.

The veterans, three of whom are still living and received the honor in person, were recognized for their valor during major combat operations in World War II, the Korean War and the Vietnam War.

“Their courage almost defies imagination,” Obama said during a solemn ceremony in the East Room. “When you read the records of these individuals, it's unimaginable the valor they displayed ... running into bullets, charging machine-gun nests, holding back enemies, wave after wave, manning their posts some to their last breaths so their comrades might live.”

Ten of the 24 veterans honored on Tuesday never made it home, Obama said.

“Through their grief, the families summoned the courage to go on ... and those families join us here today,” he said.

Obama described the three honorees who are still living and able to attend the event with warm praise. He described Sergeant First Class Jose Rodela as a 76-year-old retiree who loves working on his 1975 pick-up and mowing the grass of his neighbors.

Specialist Four Santiago Erevia, 67, lives in San Antonio and often enjoys doing some push-ups to stay in shape, Obama said.

Staff Sergeant Melvin Morris, he said, is celebrating 53 years of marriage this year.

“You're going to have to give me some tips — we're not that far along yet,” Obama quipped.

Morris, 72, was one of the first soldiers to become a “green beret” in 1961 and volunteered twice for deployments in Vietnam.

While in the Chi Lang district in Vietnam in September 1969, Morris led an advance across enemy lines to retrieve a fallen comrade and single-handedly destroyed an enemy force that had pinned his battalion from a series of bunkers. He was shot three times as he ran back toward friendly lines with the American casualties, but did not stop until he reached safety.

The same month in Phuoc Long Province of Vietnam, Rodela commanded his company throughout 18 hours of continuous contact when his battalion was attacked and taking heavy casualties. Although wounded, Rodela repeatedly exposed himself to enemy fire to attend to the fallen and eliminate an enemy rocket position.

Just a few months earlier, Erevia was serving as a radio-telephone operator during a search-and-clear mission near Tam Ky City, Vietnam, when his unit came under heavy fire. While crawling from one wounded soldier to the next, Erevia used two M-16s and several grenades to destroy four enemy bunkers and their occupants.

“For your comrades and your country, you refused to yield, and on behalf of a grateful nation, we want to thank you for inspiring us then and now,” Obama said.

The 21 other recipients of the Medal of Honor on Tuesday who received it posthumously include: Sergeant Candelario Garcia, Specialist Four Leonard Alvarado, Staff Sergeant Felix Conde-Falcon, Specialist Four Ardie Copas, Specialist Four Jesus Duran, Corporal Joe Baldonado, Corporal Victor Espinoza, Sergeant Eduardo C. Gomez, Private First Class Leonard M. Kravitz, Master Sergeant Juan E. Negron, Master Sergeant Mike C. Pena, Private Demensio Rivera, Private Miguel A. Vera, Sergeant Jack Weinstein, Private Pedro Cano, Private Joe Gandara, Private First Class Salvador Lara, Sergeant William Leonard, Staff Sergeant Manuel Mendoza, Sergeant Alfred Nietzel and First Lieutenant Donald Schwab.

Medals of Honor — the nation's highest award for valor in combat — are given sparingly. Since the late 1990s, the military has tried to ensure that deserving veterans have not been overlooked by administrative error, oversights or as a result of new evidence.

The 24 veterans honored Tuesday were discovered after Congress called for a review of Jewish-American and Hispanic-American veteran war records to ensure those deserving of the Medal of Honor were not denied because of prejudice. During the review, records of several soldiers of neither Jewish nor Hispanic descent also were found to display criteria worthy of the Medal of Honor.