FBI chief in Nevada says motive behind Las Vegas concert massacre is still a mystery

Federal authorities continue to search for the motive that drove a gunman to open fire on country music festival this fall, a bloody rampage that left 58 people dead and hundreds wounded.

FBI Special Agent in Charge Aaron Rouse told the Las Vegas Review-Journal on Wednesday that investigators still couldn’t say what made 64-year-old Stephen Paddock begin firing into a crowd of 22,000 at the Route 91 Harvest Festival on Oct. 1.

“Ours is focusing a large part on the why, OK? Which is what everybody wants to know,” Rouse said. He said federal authorities expected to issue a report sometime next year.

Since the shooting, law enforcement officials have been largely quiet about Paddock’s motives, and the lack of information has fueled several conspiracy theories in the nearly three months since the massacre.

But Rouse told the Review-Journal that investigators think Paddock acted alone.

“I believe that there is one person and one person alone to blame for what happened on 1 October, and that is Stephen Paddock,” Rouse said.

He outlined the efforts the agency had undertaken to try to discover a motive for Paddock, including interviewing 400 people about the gunman, using 400 specialists, and following up on 1,500 leads in Las Vegas and an 500 more worldwide.

“We didn’t leave anything uncovered,” Rouse said. “And again, the casinos, with their support, let us track down a lot of information of who may have had contact with that person. And it was very helpful to us.”

Rouse didn’t address Paddock’s penchant for gambling, but Clark County Sheriff Joe Lombardo said in an 8 News interview about a month after the shooting that Paddock “was going through some bouts of depression” and that the gambler was “status-driven.”

Lombardo said Paddock had been losing money for two years and had been showing signs of depression.

“Since September 2015, he’s lost a significant amount of wealth, and I think that might have been a determining factor on what he was determined to do,” Lombardo said.

Paddock was known to play video poker and gamble large sums of money on the machines, and played at several properties on the Las Vegas Strip as well as at casinos in Mesquite and Reno. Rouse didn’t address the state of Paddock’s finances at the time he settled into his room on the 32nd floor of the Mandalay Bay hotel and began firing into the crowd at the concert across the street.

Authorities have acted on search warrants at Paddock’s homes in Mesquite and in Reno. Several search warrants remain sealed and a hearing is scheduled next month to determine whether the contents of those warrants should be unsealed. Several media outlets — including the Los Angeles Times — have also filed lawsuits seeking the release of the 911 tapes from the night of the shooting.

david.montero@latimes.com

Twitter: @davemontero