Surveillance video caught the heart-stopping moment a man lost control of his electrified wheelchair and tumbled face-first onto Washington, D.C., subway tracks before good Samaritans pulled him to safety.

U.S. Army Spc. Michael Menchaca was coming down the escalator July 4 at the Metro Center station when he "saw something go over the track."

"I went to go see … look down there and there was a guy strapped to his wheelchair," Menchaca told ABC News affiliate WJLA-TV.

The man was apparently trying to read a sign across the tracks when his wheelchair rolled forward and fell off the platform, landing inches away from the high-voltage third rail of the Metro's central hub station.

Menchaca was the first person to jump onto the tracks to assist the unidentified man.

"I just jump down there, start helping him out," Menchaca said. "Tried picking him up but realized he was still seat belt-strapped to his wheelchair."

Menchaca struggled to free the man from his seat belt, worried that a train could be barreling down on them at any moment.

"Every second felt like 30 seconds," he said.

That's when a passenger from the opposite platform jumped into action and leaped over both third rails to help Menchaca. A third good Samaritan descended onto the tracks and, together, the three men were able to pull the man to safety.

The unidentified man only suffered minor injuries and now Menchaca is now being considered for the Soldier's Medal, the Army's highest peacetime award.

"It was just the right thing," Menchaca said. "Pretty much like anyone else would have done."

ABC News