"(The casinos) know whether he lost money because he never would have gambled for a second without putting the card in", Eric Paddock said.

At least 59 people were killed and 527 injured at the Route 91 music festival on Sunday night, in the worst mass shooting in USA history.

Lombardo also said Paddock had cameras in his room - including one apparently monitoring the corridor approach.

The Las Vegas gunman who killed 58 people and himself in the deadliest mass shooting in modern USA history stockpiled weapons and ammunition over decades, and meticulously planned the attack, authorities believe. Armstrong said he's baffled by why he was so open with a stranger, but "my job is to put people easily and try to help them buy a auto".

The room, which goes for $590 (€500), was given to Paddock free because he was a good customer who wagered tens of thousands of dollars each time he visited the casino, the person said.

The gunman behind the deadliest mass shooting in modern USA history led a secret life that has so far thwarted investigators trying to figure out a motive for the attack.

Margie Newman had just settled in to her 26th-floor hotel room at the Mandalay Bay Resort & Casino on the Las Vegas Strip on Sunday night when she heard what she thought was construction noise outside after 10 p.m.

But what motivated Paddock to kill dozens of strangers and whether he had help remains a mystery. "That's the one in this one, and we are not there yet", FBI Deputy Director Andrew McCabe was quoted by The Associated Press as saying.

Boston Police Commissioner William Evans says authorities will step up security for concerts and sporting events in the city following the shooting in Las Vegas.

Asked if investigators had determined why Paddock carried out the attack, he said, 'We are not there yet.' He suggested that was unusual.

"Somehow or another we ended up talking about bad relationships, and he confided that he was depressed and his life was miserable", Armstrong said.

"Australia will support the U.S. authorities in their investigation in whatever way we can, but we have not had contact with Marilou Danley directly". Their mother spoke with him about two weeks ago, and when he found out recently that she needed a walker, he sent her one, Eric Paddock said.

When we arrived at around 5pm local time, police had re-opened the cordon, but the house was boarded up.

Danley's sisters, who were not identified by name and whose faces were blurred, added that Danley would willingly cooperate with investigators. "Since he has utilized firearms in previous crimes, has employed violence in attempting to evade arrest and has been diagnosed as being psychopathic, Paddock should be considered extremely unsafe", said Palmer M. Baken Jr., agent in charge of the Phoenix FBI office.

"On face value, you've got to make the assumption he had to have some help at some point, and we want to ensure that that's the answer".

United States reports and officials said she is either in the Philippines or Japan, although neither country was able to confirm her whereabouts. The FBI is working with Philippine authorities to get more details. "I was grateful, but honestly I was anxious at first that the unexpected trip home and then the money was a way of breaking up with me".

Meanwhile, President Donald Trump met privately with victims of the shooting at a Las Vegas hospital Wednesday.

"He's a sick, demented man", Trump said.

Paddock's father was Benjamin Hoskins Paddock, a serial bank robber.

A Federal Bureau of Investigation official in Las Vegas, meanwhile, said no one has been taken into custody.

Separately, a GoFundMe for the victims of Las Vegas has raised nearly $9 million as of Wednesday afternoon.

"From October 2016 to September 28, 2017, he purchased 33 firearms, majority of them rifles", Snyder said.

"It was pre-planned, extensively, and I'm pretty sure that he evaluated everything that he did in his actions, which is troublesome", Joseph Lombardo, the sheriff of the Las Vegas Metropolitan Police Department, said. Bruce said his brother was a law-abiding citizen who never did anything violent prior to the shooting.

In explaining his theory, the sheriff mentioned Mr Paddock's arsenal of 47 guns and a "plethora" of ammunition, plus he's two Nevada residences.

Authorities released police body camera video that showed the chaos of the attack as officers tried to figure out the location of the shooter and shuttle people to safety. The first 911 call was received at 10.08pm, and it took police 75 minutes to enter Paddock's hotel room in Mandalay Bay.