Vegas police close investigation into Strip shooting, with FBI report to come

Las Vegas police say after hundreds of interviews and thousands of hours of investigative work, they are confident there is no evidence of a conspiracy or a second gunman in the October 2017 massacre that left 58 dead, but the shooter's motives are less clear.

Sheriff can't ascribe the shooter's motives but personally considers it a 'terrorist attack'

Clark County Sheriff Joe Lombardo says he personally considers the mass shooting of concertgoers at the Route 91 Harvest Festival in Las Vegas to be a terrorist attack. (John Locher/Associated Press)

More than 10 months after the deadliest mass shooting in modern U.S. history, police say they are closing their investigation without answering the key question: What drove a gunman to unleash a hail of gunfire that killed 58 people and wounded hundreds more?

But authorities say after hundreds of interviews and thousands of hours of investigative work, they are confident there is no evidence of a conspiracy or a second gunman.

Clark County Sheriff Joe Lombardo said the shooter was "an unremarkable man" who showed signs of a troubled mind leading up to the Oct. 1, 2017, massacre on the Las Vegas Strip, but nothing alerted authorities in the preceding weeks or months.

"We have not been able to definitively answer the 'why,'" Lombardo said.

"Without a manifesto or even a [suicide] note to answer questions, the totality of the information that has been gathered leads us to only make an educated guess as to the motives of Stephen Paddock," he added.

In this Oct. 1, 2017, file photo, police run toward the scene of a shooting near the Mandalay Bay hotel on the Las Vegas Strip. Vegas police don't anticipate charging any individuals in connection with the shooting. (John Locher/Associated Press)

Paddock, who fired across Las Vegas Boulevard from a hotel room on the 32nd floor of the Mandalay Bay hotel into a concert crowd of 22,000 people, was the only gunman, Lombardo said.

Lombardo said that with the closure of the Las Vegas Metropolitan Police Department's 10-month investigation, no one else will be charged in connection with the deadliest mass shooting in modern U.S. history, including his girlfriend, who was questioned extensively.

The FBI's behavioral analysis unit is expected to release a psychological profile of Paddock later this year, said Lombardo.

While the cause remains elusive, the sheriff was not shy stating his personal opinion when directly asked by a reporter.

"I would personally call it a terrorist attack. It had an influence on a certain demographic of people, intended to cause harm," said Lombardo, who allowed that it didn't meet the standard FBI definition of the term.

Lombardo also said the police "have no knowledge" of radicalization of the shooter.

Officials have said the attack had no link to international terrorism, but hotel owner MGM Resorts International last month invoked a provision of a federal law enacted after the Sept. 11 terror attacks.

The company wants federal courts to qualify the shooting as an act of terrorism and to declare the company has no liability to survivors or families of slain victims.

Federal charges over ammo sale

On Friday, the National Consortium for the Study of Terrorism and Responses to Terrorism, which receives funding from the Department of Homeland Security, released its annual global terrorism report.

In describing the Nevada shooting, the report refers to Paddock as "an anti-government extremist," referring to witness accounts that he had expressed anger over 1990s standoffs in Waco, Texas, and Ruby Ridge, Idaho. 

"We're aware of some of the comments made to various individuals," Lombardo said when asked by a reporter of accounts of the shooter's anti-government views.

Paddock's wealth had diminished substantially in the preceding months, Lombardo said, through gambling losses, purchases of firearms and money given to his girlfriend, but police can't specifically pinpoint when he began plotting the attack.

Police seized a number of items from Paddock's hotel room but have not located a missing hard drive from his laptop. He regularly removed hard drives from his computers, police were told.

Earlier this year, federal prosecutors brought criminal charges against a man who they say sold armour-piercing bullets.

Authorities have said the man, Douglas Haig, sold Paddock 720 rounds of tracer bullets. He has pleaded not guilty.

Lombardo called the investigation a "monumental task," and police have released 13 batches of investigative documents, 911 audio, police reports, witness statements and video over the last three months.

They have illustrated chaos, heartbreak and heroism from police, first-responders, concertgoers and more.

Body camera recordings made public earlier showed officers using explosives to blast through the door of a 32nd floor hotel suite to find Paddock dead on the floor from a self-inflicted gunshot. Assault-style weapons fitted with rapid-fire "bump stock" devices were strewn about the suite.

The devices, which can allow a semi-automatic weapon to approximate the firing capabilities of an automatic, came to wider attention as a result of the shooting.

Donald Trump and congressional Republicans balked at a legislative ban of bump stocks, but the president has backed regulations from the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives that would effectively outlaw them.

With files from CBC News