Oct. 9 (UPI) -- Las Vegas gunman Stephen Paddock shot and injured a hotel security guard before he opened fire on a crowd of concert goers, not after as previously thought, investigators said Monday.
During an afternoon news conference, Las Vegas Metropolitan Police Department Sheriff Joe Lombardo laid out a timeline for the shooting Oct. 1 that left 58 people dead and more than 500 injured.
He said Mandalay Bay Resort & Casino security guard Jesus Campos was shot at 9:59 p.m., minutes before Stephen Paddock opened fire at the country music festival crowd from his window. Previously, police said they believed Campos was shot while attempting to stop the shooting.
Lombardo said police were unaware Campos had been shot "until they met him in the hallway after exiting the elevator" at the hotel.
Lombardo also confirmed the shooter's brother had traveled to Las Vegas and was meeting with investigators. They're hoping he might shed some light on a possible motive for the attack.
Eric Paddock told the Las Vegas Review-Journal spoke with police for 5 hours after he arrived from Florida on Saturday.
"I'm here to help them move forward with their investigation," he said. "I want to help them understand what they're seeing."
Eric Paddock's arrival comes at a time when Las Vegas police still don't have a firm grasp on what led his brother to commit the deadliest mass shooting attack in modern U.S. history.
Eric Paddock said he plans to have the shooter's body cremated and will use his brother's assets to create a trust for the victims of the attack.
Officials said they have followed more than 1,000 leads in the case.
CNN reported Monday that Paddock interacted with authorities in 2013 as part of a civil lawsuit against the Cosmopolitan Hotel in Las Vegas, where he said he'd slipped and fell two years earlier.
Paddock said he'd been prescribed Valium "for anxiousness" and described himself as the "biggest video poker player in the world." When asked if he used the hotel pool, Paddock said, "I do not do sun."
In the 97-page court deposition, the gunman said he regularly received alcoholic beverages and was "comped" hotel rooms most of the time, which are both standard practices by Las Vegas casinos to draw major gamblers.
"I'll gamble all night, I sleep during the day," he said in his testimony.
CNN reported that the deposition was turned over to the FBI.
Authorities questioned a number of people who knew Paddock, including his girlfriend and family members. Monday, a woman who formerly worked for the shooter described him as a man who "liked to make people happy."
"He actually cared about everybody," Lisa Crawford, who worked for Paddock managing an apartment, told ABC News. "He tried to make people happy. He tried to make people care and I don't know what happened to him."
Former Las Vegas Mayor Oscar Goodman offered a different view.
"I know he is rotting in hell in eternal damnation, and I hope that [Josef] Mengele is his roommate," he told CNN, referencing a Nazi SS officer.
The city of Las Vegas honored the victims of the shooting Sunday night by darkening its famous Las Vegas Boulevard for 11 minutes, the length of time of the attack. Every casino and business switched off their lights to pay tribute.