Imran Yousuf, a 24-year-old bouncer at the Pulse nightclub, heard the gunfire break out early Sunday morning.
"The initial one was three or four (shots). That was a shock. Three of four shots go off and you could tell it was a high caliber," Yousuf, a 'Hindu' whose familyhad immigrated to Guyana from India four generations ago, told CBS News.
"Everyone froze. I'm here in the back and I saw people start pouring into the back hallway, and they just sardine pack everyone."
Yousuf knew just beyond that pack of panicked people - was a door - and safety. But someone had to unlatch it.
"I'm screaming 'Open the door! Open the door!'" Yousuf said. "And no one is moving because they are scared."
"There was only one choice - either we all stay there and we all die, or I could take the chance, and I jumped over to open that latch and we got everyone that we can out of there."
"I wish I could've saved more," CBS News quoted him as saying. "...There's a lot of people that are dead."
Yousuf served as an engineer equipment electrical systems technician in the Marine Corps from June 2010 to May 2016, according to service officials. He was deployed to Afghanistan in 2011. He was last assigned to 3rd Marine Logistics Group.
He posted a message on his Facebook page saying he "just reacted."
"There are a lot of people naming me a hero and as a former Marine and Afghan veteran I honestly believe I reacted by instinct," he wrote.
