Pulse nightclub in Orlando, site of a Saturday night massacre that left 50 dead and more than 50 wounded, was founded in a spirit of love and tribute. Its name honors the memory of founder c0-founder Barbara Poma's brother John, who died in 1991 after battling HIV.

"For nearly 12 years, John’s Pulse has been reverberating throughout the club, and Pulse looks forward to 12 more successful years of raising awareness, education, and prevention of the HIV virus," according to a history of the club on its web site. "Our mission at Pulse is to continue to raise the bar of awareness and be a part of our community in any way possible."

MORE: Atlanta airport chaplain offers solace after Orlando nightclub shooting

Authorities on the scene after the Pulse nightclub shooting. Photo: WFTV

Credit: Jennifer Brett

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Credit: Jennifer Brett

The gunman has been identified; please return for updates.

Poma and partner Ron Legler opened the club in 2004.

An image from the section of the Pulse nightclub site that shares its history.

Credit: Jennifer Brett

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Credit: Jennifer Brett

"They both believed in a vision that it was important to create an atmosphere that embraced the gay lifestyle with décor that would make John proud," the club's history reads. "Most importantly, they coined the name Pulse for John’s heartbeat – as a club that is John’s inspiration, where he is kept alive in the eyes of his friends and family."

The club's Facebook page has been filling with tributes and messages of love since its harrowing update seven hours ago: "Everyone get out of pulse and keep running."

""From an Orlando resident: (I think I speak for many when I say) we appreciate all the love and condolences from ALL over the word!" Kelly Drabczyk posted. "And to my Orlando family/anyone who was on the scene or by downtown-- let's stay strong, I love you all-- and I am damn proud to call Orlando home!!"

"I'm here in Orlando watching the local news and my heart is absolutely breaking," Yamarilis Gonzalez added. "This isn't right or fair and I don't understand why these things but I pray for all those involved. Please know that there are many praying for you all. Lots of love to everyone involved."

And from Coco Lopez: "To the families, friends and the LGBT Community in Orlando and all over the world that has been affected by tragedies such like these..Healing, strength and Compassion..We are with you Pulse Orlando..ONE LOVE!!"