(Recasts with latest law enforcement news conference, officials say death toll confirmed at 58 plus the gunman, 12 weapons found in hotel suite equipped with 'bumper stocks', 47 guns recovered altogether, purchased in four states, crime scene photos are authentic, paragraphs 1, 11-12, 15, 17)

* Live-in companion sought for questioning

* Wire transfer of $100,000 under examination

* Trump calls gunman 'a sick, demented man'

* Killer amassed dozens of weapons, explosives, ammunition

* Massacre stirs gun control debate

By Sharon Bernstein and Alexandria Sage

LAS VEGAS, Oct 3 (Reuters) - The investigation into the motives of a Las Vegas retiree who killed 58 people in the worst mass shooting in modern U.S. history turned on Tuesday to the gunman's girlfriend in the Philippines, where she turned up after the massacre, authorities said.

Stephen Paddock, who killed himself moments before police stormed the hotel suite he had transformed into a sniper's nest on Sunday night, left no clear clues as to why he staged his attack on an outdoor concert below the high-rise building.

But law enforcement authorities were hoping to obtain some answers from a woman identified as Paddock's live-in companion, Marilou Danley, who Clark County Sheriff Joseph Lombardo said was a "person of interest" in the investigation.

Lombardo, who said on Monday Danley was believed to be in Tokyo, told reporters on Tuesday she had been located in the Philippines and the Federal Bureau of Investigation was in the process of trying to bring her back to the United States.

"We are in conversations with her," he told an afternoon news briefing. He reiterated police had no other suspects in the shooting itself.

Danley, an Australian citizen reported to have been born in the Philippines, had been sharing Paddock's condo at a retirement community in Mesquite, Nevada, about 90 miles (145 km) northeast of Las Vegas, according to police and public records.

Investigators were examining a $100,000 wire transfer Paddock, 64, sent to an account in the Philippines that "appears to have been intended" for Danley, a senior U.S. homeland security official told Reuters on Tuesday.

The official, who has been briefed regularly on the probe but spoke on condition of anonymity, said the working assumption of investigators was that the money was intended as a form of life insurance payment for Danley.

The official said U.S. authorities were eager to question Danley, who described herself on social media websites as a "casino professional," mother and grandmother, about whether Paddock encouraged her to leave the United States before he went on his rampage.

The official said investigators had also uncovered evidence that Paddock may have rehearsed his plans at other venues before ultimately carrying out his attack on the Route 91 Harvest country music festival from the 32nd floor suite of the Mandalay Bay hotel on the Las Vegas Strip.

ARSENAL RECOVERED

Fresh details about the massacre and the arsenal Paddock amassed emerged on Tuesday.

Police said Paddock strafed the concert crowd with bullets for nine to 11 minutes before taking his own life, and had set up cameras inside and outside his hotel suite so he could see police as they closed in on his location.

A total of 47 firearms were recovered from three locations searched by investigators - Paddock's hotel suite, his home in Mesquite, and another property associated with him in Reno, Nevada, according to Jill Snyder, special agent for the U.S. Bureau of Alcohol Tobacco and Firearms (ATF).

Snyder said 12 of the guns found in the hotel room were fitted with so-called bump-stock devices that allow the guns to be fired virtually as automatic weapons. The devices are legal under U.S. law, even though fully automatic weapons are for the most part banned.

The rifles, shotguns and pistols were purchased in four states - Nevada, Utah, California and Texas - Snyder told reporters at an evening news conference.

A search of Paddock's car turned up a supply of ammonium nitrate, a fertilizer that can be formed into explosives and was used in the 1995 Oklahoma City bombing of a federal office building that killed 168 people, Lombardo said earlier.

Police also confirmed that photos widely published online showing the gunman's body, his hands in gloves, lying on the floor beside two firearms and spent shell casings, were authentic crime-scene images obtained by media outlets. An internal investigation was under way to determine how they were leaked.

Video footage of the shooting spree on Sunday night caught by those on the ground showed throngs of people screaming in horror, some crouching in the open for cover, hemmed in by fellow concert-goers, and others running for cover as extended bursts of gunfire rained onto the crowd of some 20,000.

Police had put the death toll at 59 earlier on Tuesday, not including the gunman. However, the coroner's office revised the confirmed tally to 58 dead, plus Paddock, on Tuesday night.

More than 500 people were injured, some trampled in the pandemonium. At least 20 of the survivors admitted to one of several hospitals in the area, University Medical Center, remained in critical condition on Tuesday, doctors said.

The union representing firefighters disclosed that a dozen off-duty firefighters who were attending the music festival were shot while trying to render aid to other spectators, two of them while performing cardiopulmonary resuscitation on victims.

"This is a true feat of heroism on their part," said Ray Rahne of the International Association of Fire Fighters.

WHAT DROVE GUNMAN?

But the central, unanswered question to the bloodshed was what drove the gunman's actions.

Federal, state and local investigators have found no evidence that Paddock had even incidental contacts with foreign or domestic extremist groups, and reviews of his history showed no underlying pattern of criminal behavior or hate speech, the homeland security official said.

While investigators had not ruled out the possibility of mental illness or some form of brain injury, "there's no evidence of that, either," the official said.

Paddock's brother, Eric, has said he was mystified by the attack.

"It just makes less sense the more we use any kind of reason to figure it out," Eric Paddock said in a text message on Tuesday. "I will bet any amount of money that they will not find any link to anything ... he did this completely by himself."

He said the family did not plan to hold a funeral for his brother, who was not religious, saying it could attract unwanted attention. He described his brother as a financially well-off enthusiast of video poker and cruises, with no history of mental health issues.

President Donald Trump told reporters on Tuesday that Paddock had been "a sick man, a demented man."

GUN DEBATE STIRRED

The attack stirred the fractious debate about gun ownership in the United States, which is protected by the Second Amendment of the Constitution, and about how much that right should be subject to controls.

Sunday's shooting followed the massacre of 26 young children and educators in Newtown, Connecticut, in 2012, and the slaying of 49 people at a gay nightclub in Orlando last year.

The latter attack was previously the deadliest mass shooting in modern U.S. history.

Democrats reiterated what is generally the party's stance, that legislative action is needed to reduce mass shootings. Republicans, who control the White House and both chambers of Congress, argue restrictions on lawful gun ownership cannot deter criminal behavior.

"We'll be talking about gun laws as time goes by," said Trump, who strongly supported gun rights during his presidential campaign.

Paddock seemed unlike the troubled, angry young men who experts said have come to embody the mass-shooter profile in the United States.

Public records on Paddock point to an itinerant existence across the U.S. West and Southeast, including stints as an apartment manager and aerospace industry worker. He appeared to be settling in to a quiet life when he bought a home in a Nevada retirement community a few years ago.

(Additional reporting by Lisa Girion in Las Vegas, Jonathan Allen and Frank McGurty in New York, John Walcott, Susan Cornwell, Doina Chiacu and Jeff Mason in Washington, Bernie Woodall in Fort Lauderdale, Florida, Jon Herskovitz in Austin, Texas and Brendan O'Brien in Milwaukee; Writing by Steve Gorman and Scott Malone; Editing by Frances Kerry, Jonathan Oatis and Andrew Hay)

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