A U.S. Marine veteran saved dozens of lives during the terrorist attack on a gay nightclub in Orlando over the weekend.
Imran Yousef, a bouncer at Pulse nightclub who served in Afghanistan, immediately recognized the sound of gunfire when mass killer Omar Mateen began shooting 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," Yousef 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."
Yousef’s military training kicked in immediately, allowing him to react quickly while victims stood paralyzed. He told CBS that he knew there was a door behind the fear-stricken crowd.
"I’m screaming ‘Open the door! Open the door!’ And no one is moving because they are scared," he said. "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."
Yousef estimated that about 70 people were able to leave safely through that exit.
"I wish I could have saved more," he said tearfully to CBS. "There are a lot of people dead."
Forty-nine people were killed inside of Pulse nightclub Sunday, marking the worst mass shooting in U.S. history and the deadliest terrorist attack since September 11, 2001. Mateen pledged allegiance to ISIS during the attacks.
A doctor who works at the hospital that treated those wounded from the shooting said the death toll could rise, as six patients remain in critical condition.
Yousef wrote in a Facebook post Monday that he "just reacted," the Marine Corps Times reported.
"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. "While it might seem that my actions are heroic, I decided that the others around me needed to be saved as well and so I just reacted."