Updated

The crowd of country music fans targeted by the Las Vegas gunman happened to include many off-duty police and firefighters. They sprang into action when bullets started flying.

The rampage that killed 58 people and left nearly 500 injured could have been deadlier without the quick thinking of officers who treated the wounded and directed paramedics to the most critically hurt victims.

Fred Rowbotham is an officer from Chula Vista, California. He was celebrating his 45th birthday at the music festival. When the gunfire began, he says, his instincts took over. He got pelted by shrapnel as he helped dozens of people get to safety.

Dr. Douglas Fraser of University Medical Center of Southern Nevada says it's invaluable when someone can apply pressure to a wound or place a tourniquet.