His brother, Eric, who lives in Orlando says he was dumbfounded by the incident.
"There's absolutely no way I can even conceive that my brother would shoot a bunch of people that he doesn't even know," said Eric Paddock.
His 57-year-old brother spoke to us from the sidewalk in front of his Orlando home saying his older brother had once been an accountant, they owned real estate together and he had recently moved him from Melbourne back to Las Vegas.
"Yes, he had a couple of guns. I mean, it's legal to own a couple of guns in the United States. He did not own machine guns that I knew of in any way, shape or form. He didn't own them when I moved him to Melbourne," he said.
Paddock says his brother had been married at one time, had no children and had a girlfriend of two years.
He also says his brother was a professional video poker player who won big money and cars at Las Vegas casinos.
"He was a wealthy guy and he liked to play video poker. He liked to go on cruises," he said.
His brother did confirm their father was a bank robber who broke out of prison in the late 1960's and was once on the FBI's 10 Most Wanted List.
"His name is Benjamin Hoskins Paddock-- I believe is his name. I didn't know him. We didn't know him. There's no, he was in jail and broken out of jail and you'll find out, it's a wonderful story," he said.
His brother also says claims by ISIS are bogus.
"Steve had nothing to do with any political organization, religious organization. No white supremacist, nothing, as far as I know," he said.
Paddock's niece Nicole Paddock lives in East Orlando, according to News 6 in Orlando. A reporter who spoke to her said she was "shocked and disturbed" to learn that her uncle was identified as the gunman.
Stephen Paddock, 64, was found dead in a hotel room with as many as 10 firearms, police said. They think he killed himself before police broke into his room.
Authorities say that 406 people were taken to hospitals and 50 of those are dead, including an off-duty Las Vegas police officer. His name was not immediately released.