The U.S. Navy confirms that a veteran Christopher Roybal was killed in the attack. He was from San Francisco and he served in the Navy for five years as a master-at-arms.
His wife, Dixie Roybal, said he died from a gunshot wound to the chest. The family is currently trying to figure out how to transport his body to Corona, California, she said.
Dixie Roybal said her 28-year-old husband was an explosive dog handler in the Navy and he adopted their dog out of the Navy but she died a few months ago.
"He is a guy that could always put a smile on your face ... after all the stuff he had been through," said David Harman, who founded a company that owns the Colorado gym where Roybal worked, according to AP.
AP writes that Roybal worked at Crunch Fitness in Corona and Riverside, California, before he moved at the beginning of the year to help open franchises in Colorado Springs.
"He was the guy who if your car broke down in the middle of the night, you could call him and he would come help you," Harman said. "He is that guy who would find solutions, not report on problems."
Harman said Roybal served in Afghanistan and was coping with the loss of a friend who was killed by an improvised explosive device, AP writes. Roybal adopted his friend's bomb-sniffing dog, Bella, but was devastated when she died of old age.
Roybal mentioned the dog in a July 18 Facebook post that also included a lengthy description of his experience getting shot at in combat, according to AP.
He ends the post: "What's it like to be shot at? It's a nightmare no amount of drugs, no amount of therapy and no amount of drunk talks with your war veteran buddies will ever be able to escape. Cheers boys."
Roybal's co-worker, Robert Alexander, said he fell asleep with the television on Sunday night and awoke to the sound of gunshots coming from the speaker. When he remembered that Roybal had gone to Las Vegas for his birthday, he immediately called him but no one answered, AP adds.
He heard Monday morning that his friend had been killed.
"There's been several times I've had to just walk out of the club and have a good cry, go get in my car," Alexander said. "And I just drove down the street this morning, just go have a good cry 'cause it's tough."
Alexander described Roybal as a "goofball" who was full of energy and had an infectious smile.
"I just had such a fun time any time I was able to interact with him. ... Chris had that attraction power. He had the ability to make people want to hang around him," Alexander said.