They were dangerously low on ammunition. The staff sergeant picked up the last belt of ammunition and started to fire.

"Everything was a target at that point. There was movement everywhere. The muzzle flashes were everywhere. You just couldn't pick them out fast enough," Romesha said.

"I tried to hold it as long as I could, but when you're the only machine gun talking on the COP at that point, you start drawing quite a bit of attention."

Out of ammunition and under fire from all sides, Romesha failed in his mission to help Gallegos, Larson and the others.

"I called Gallegos and told him I was sorry," he said recently, pausing as he was overwhelmed by the memory.

"I just told him I was sorry. ... I just couldn't hold it anymore. Ran out of ammo and that position was compromised. I just couldn't put enough effective fire down for them."

Chaos was continuing elsewhere on the base. The roughly 20 Afghan soldiers based with Bravo Troop had fled or were hiding, leaving just the American troops to try to battle back.

Maybe it was the adrenaline. Or maybe it was total concentration on trying to save the men in the Humvee.

Whatever it was, Romesha never felt the injury caused by the RPG that had minutes earlier knocked him into Gregory.

"Dude, you have a hole in your arm," Rasmussen said as Romesha arrived back at the barracks to regroup his soldiers.

As Rasmussen bandaged the staff sergeant's arm, something much more serious, much more dangerous was playing out: Taliban militants had breached the base.

The message went out on the radio: ENEMY IN THE WIRE.

'Stay away'

Inside the barracks, Romesha was assessing who was still alive, who of the wounded could fight and how much ammunition was left.

Sgt. Joshua Hardt approached Romesha with an idea: He would take two soldiers, grab a Humvee outfitted with a .50-caliber machine gun and make a run to try to save the five men pinned down.

Romesha knew it would be a hard fight for Hardt. He talked to him about finding a good position for the truck to fire from.

Hardt and the soldiers ran for the truck. Once inside, he radioed Gallegos to let him know of their plan as Romesha listened.

"This isn't a good spot. You can't do a lot. Stay away. Stay away," Gallegos told Hardt.

But the sergeant pressed on ... until an RPG exploded near the Humvee.

Now the Humvee was stuck, and the militants were targeting them with more grenades.