After Omar Mateen opened fire on Pulse nightclub in Orlando, fear struck deep in one South Florida community for a particular reason: the man who carried out the worst mass shooting in modern American history had been one of their own protectors.

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In fact, just hours after Mateen finished his Saturday shift as a security guard at PGA Village, a gated golf course community, he stepped into the club in the early hours of June 12, 2016, and opened fire. He killed 49 people and wounded 53. 
>> Bios: Pulse shooting victims

“We thought, ‘Imagine if he’d gone off on all of us,’” one resident told The Palm Beach Post recently.

The Worst Mass Shootings in US History

Read the full story at the Palm Beach Post.

ORLANDO, FL - JUNE 13:  People hold candles during a memorial service at the Dr. Phillips Center for the Performing Arts for the victims of the Pulse gay nightclub shooting where Omar Mateen allegedly killed 49 people, June 13, 2016 in Orlando, Florida. The mass shooting killed at least 49 people and injuring 53 others in what is the deadliest mass shooting in the country'•s history.  (Photo by Joe Raedle/Getty Images)

Credit: Joe Raedle

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Credit: Joe Raedle