There were many tragic moments caught on film during the massacre at Las Vegas's Route 91 Harvest Festival Sunday night (Oct. 1). However, one iconic picture uniquely captured the panic of the moment: That of nurse Lorisa Loy pushing George Cook, a complete stranger in a wheelchair, in an attempt to flee the terrifying scene.

CBS This Morning's DeMarco Morgan detailed the story behind the photo.

Cook, a single father who lives in San Francisco with his two school-aged children, was trying to figure out what to do when the shots began. "Do I get on the ground? You know, jump out of my chair and get on the ground or stay in my chair? I chose to stay in the chair," he relates.

Loy's daughter, Meghan, initially tried to help Cook by pushing his chair. However, Loy assessed the situation and took over so her daughter could get away. After quickly introducing herself to Cook, she pushed him out of the path of the bullets.

"There's no way he could maneuver himself," she explains. "There was rubbish everywhere ... beer cans and trash, all sorts of stuff was on the ground, but we were able to push through that."

Loy suffered a sprained ankle as a result, but continued to assist others in need of first aid.

Nobody was more grateful for the brave nurse's actions than Cook. "I'm a single dad with two kids at home so it was real important that I'm alive," he says. "Maybe that's why this happened. Maybe that's why this person was sent to save me, to be there for the kids."

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