Images show inside of Las Vegas shooter’s hotel room [Warning: Graphic Content]

It took nine to 11 minutes of gunfire for Stephen Paddock to carry out the deadliest mass shooting in modern US history.

From his 32nd-floor window at a Las Vegas hotel, Paddock fired a barrage of bullets at 22,000 concertgoers below — an attack that appears to have been meticulously planned.

The gunman checked into the room days in advance, stocked a cache of weapons there and set up cameras inside his hotel suite and in the hallway.

The first call reporting shots fired came at 10:08 p.m. Sunday, and the gunfire didn’t stop until at 10:19 p.m., Clark County Undersheriff Kevin McMahill said. The shooting went off and on for nine to 11 minutes, he said.

The massacre left 58 people dead and another 500 people with gunshot wounds or stampede injuries.

President Donald Trump landed in Las Vegas just after 9 a.m. (noon ET) Wednesday as investigators continued to search for clues as to the gunman’s motive.

Police believe Paddock acted alone when he sprayed spray gunfire on the crowd at the Route 91 Harvest festival, but it’s still not known why.

Authorities are hoping to find answers when Paddock’s girlfriend, Marilou Danley, is questioned. She returned to the United States Tuesday night from the Philippines and is being accompanied by the FBI in Los Angeles.

Clark County Sheriff Joseph Lombardo told reporters Wednesday just after 9 a.m. local time that Danley would be questioned in the next half hour at the FBI’s Los Angeles field office.

At this point, Paddock’s motive in the deadly shooting remains a mystery.

“There’s all kinds of things that surprise us on these kinds of events, that’s the one on this one,” FBI Deputy Director Andrew McCabe told CNBC. “This individual … didn’t leave the sort of immediate thumbprints you find on these kinds of attacks.”

McCabe told CNN that the FBI was looking at all possible motives and going through Paddock’s communications, financial records, associates and video surveillance.

“We will look at every one of those lanes, pull every possible thread,” he said.

The gunman had an arsenal of weapons in his hotel suite, including bump-fire stocks — legal devices that enable a shooter to fire bullets rapidly, similar to an automatic rifle.

Paddock had outfitted 12 of his firearms with the bump stocks, said the Bureau of Alcohol, Tobacco, Firearms and Explosives.

The killer also had cameras set up inside and outside the suite. Police don’t know if the devices were transmitting — the FBI is investigating their use — but the Clark County sheriff said he thinks Paddock might have used them to watch for people approaching his room. One camera looked out the peephole on the suite’s door.

The hail of gunfire stopped when security guards approached Paddock’s room at the Mandalay Bay Resort and Casino, McMahill said. Paddock turned his attention to those outside his door and fired, wounding one of them.

The guard was “very heroic” and provided police with information about the shooter’s location, McMahill said. When officers entered the hotel room, they found Paddock dead. Authorities believe he killed himself.

The girlfriend’s return

Danley, the gunman’s girlfriend, entered the Philippines September 15 and again on September 25, traveling on her Australian passport, said Maria Antoinette Mangrobang, spokeswoman for the Bureau of Immigration in the Philippines.

Danley had lived in Mesquite, Nevada, with Paddock. She was out of the country during the shooting, police said.

Mangrobang said authorities in the Philippines have been communicating with the FBI and the US Department of Homeland Security.

Paddock had wired $100,000 to the Philippines, a law enforcement source said. But officials haven’t been able to say exactly when the money transfer took place or who was the recipient. The FBI is working with Filipino authorities to determine details.

Danley’s sisters, speaking to CNN affiliate Seven Network Australia, said that Danley didn’t know anything about the shooting ahead of time and that Paddock “sent her away” before the attack.

“She was sent away so that she will be not there to interfere with what he’s planning,” one sister said.

The sisters, who were not identified by name and whose faces were blurred, added that Danley would willingly cooperate with investigators.

“Of all the people that they have interviewed … no one can put the puzzles together — no one — except Marilou, because Steve is not here to talk anymore,” one sister said. “Only Marilou can maybe help to solve this investigation and what and why he’s done this.”

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