LAS VEGAS (CBS/AP) — Investigators are trying to unravel the mass murder mystery as they uncover some new evidence in the deadly Las Vegas shooting.

Investigators say gunman Stephen Paddock was a high-rolling gambler who had even gone to the casinos over the weekend.

Paddock’s girlfriend, Marilou Danley, is considered a “person of interest” and has been speaking with police from the Philippines, where she is traveling, Sheriff Joseph Lombardo said.

While the probe into Paddock’s background included searches of two houses he owned in Nevada, some investigators turned their focus from the shooter’s perch to the festival grounds outside the Mandalay Bay hotel casino where his victims fell.

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A dozen investigators, most in FBI jackets and all wearing blue booties to avoid contaminating the scene, documented evidence at the site where gunfire rained down Sunday night and country music gave way to screams of pain and terror.

“Shoes, baby strollers, chairs, sunglasses, purses. The whole field was just littered with things,” said Nevada Attorney General Adam Laxalt, who told The Associated Press it was like a “war zone.” ”There were bloodstains everywhere.”

Paddock killed himself before a SWAT team blew off the door of his room on the 32nd floor.

During a Tuesday night press conference, authorities detailed a timeline of the shooting, indicating the gunfire started at 10:08 p.m. The gunfire went on and off from 9-11 minutes until it ceased at 10:19 p.m.

Investigators found video cameras set up inside his room and on a service cart outside it to spy anyone coming his way, Lombardo said.

What police still don’t know is what drove him to carry out the attack.

The concert grounds that turned into a killing field remain closed off as people in Las Vegas struggle to come to grips with the unspeakable tragedy that shattered the community.

Police say the 64-year-old Paddock had an arsenal of 23 weapons and thousands of rounds of ammunition in his suite at Mandalay Bay. A total of 47 firearms were recovered by authorities during from multiple locations connected to the suspect.

According to the ATF, Paddock had devices, known as a “bump stock”  attached to 12 weapons allowing semiautomatic rifles to mimic fully automatic gunfire.

What investigators don’t know is what set off the retired accountant who had no history of gun violence.

“We’re hunting down and tracing down every single clue that we can get in his background,” said Assistant Sheriff Todd Fasulo.

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From the 32nd floor, Paddock took aim at thousands of people at a music festival. As people fled in panic, fencing around the venue trapped many.

“It is what you see on TV and it is never going to be you. It is never going to happen to you and it is happening,” said Heather Gooze.

Gooze comforted 23-year-old Jordan McIldoon when he was hit. She did not know him. Using his cellphone, she called his girlfriend who sheltered in place nearby.

“She said, ‘Be honest with me, like, what’s going on?’ And I said, ‘He didn’t make it.’ I’ve been with him over an hour now. I go, ‘He’s dead,’” described Gooze. “She said to me, ‘You know, he’s the love of my life, like, are you sure?’ I said, ‘Yes.’”

Gooze sat with McIldoon’s body for hours, not wanting to leave him alone.

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Authorities say Paddock modified two guns to make them fully automatic. His rampage has sparked new conversations about gun laws in this nation.

President Donald Trump was asked about it as he left the White House Tuesday morning.

“We’ll be talking about gun laws as time goes by,” said Trump.

With hundreds hospitalized, people in Las Vegas are answering the urgent call for blood. Long lines of donors are stretching at locations across the city.

(TM and © Copyright 2017 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2017 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)

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