WARNING: GRAPHIC CONTENT 

Fifty-eight people have been killed and 515 injured after a shooting at the Route 91 Harvest Festival in Las Vegas, Nevada

The shooter has been identified as Stephen Paddock, 64, who opened fire from a 32nd floor room of Mandalay Bay Hotel after 10pm Sunday night 

Police say they breached Paddock's room and found him dead inside alongside an 'arsenal' of weapons

It took an hour and 12 minutes from the first 911 call to the moment police burst into Paddock's room  

Cops located his girlfriend Marilou Danley for questioning, but don't believe she's involved in the shooting 

He had been staying in Las Vegas since Thursday, but hotel staff who had been in and out of his room never saw signs of his weapons 

Paddock was a retired accountant and came to Las Vegas often to gamble, his brother said

NBC reports that he gambled $20,000 to $30,000 on several occasions in the past few weeks 

It's the deadliest shooting in U.S. history - eclipsing last year's massacre at Pulse nightclub in Orlando, Florida 

At least 58 people are dead and 515 injured after a 72-minute shooting by a lone-wolf gunman who unleashed thousands of rounds of ammunition onto a Las Vegas music festival from a hotel room 1,200 feet away - and more details are still coming out. 

Police say 64-year-old Stephen Craig Paddock used automatic weapons to rain down gunfire on a crowd of 22,000 people attending the Route 91 Harvest Festival Sunday night, from his room across the street in the Mandalay Bay hotel.

Headliner Jason Aldean was in the middle of his set just after 10pm when a rumble of gunfire rang out, the sounds of screams and stampeding humans cutting through the country music.

It took police an hour and 12 minutes from the first 911 call to locate Paddock in the building. They were able to figure out that the shots were coming from the Mandalay Bay, so they worked their way from the bottom up. Once they reached the 32nd floor, authorities say they knew they were in the right place. Why remains unclear, but they could have possible smelt or heard gunfire. 

They used explosives to blow the door off his room, but by then it was too late - Paddock had shot himself dead. It's unclear how long after he first started shooting that Paddock committed suicide. 

Inside the room they found an 'arsenal' including 10 rifles.

The following morning, pictures of the Mandalay Bay tower showed two windows on the 32nd floor were shattered. 

It's believed that Paddock was staying in a large suite or connected rooms, and used both to fire down on the crowd from both vantage points. Police say he used a hammer-like device to smash the windows. 

Following the shooting, police raided Paddock's home in a retirement community in Mesquite, Nevada where he lived with his girlfriend, 62-year-old Marilou Danley.  

Danley was initially called a person of interest in the shooting, because she appeared to have checked into the hotel with him. But when police called her after the shooting, they found out she has been out of the country and that Danley had used her ID to check into the hotel. They no longer believe she had anything to do with the massacre, but plan to interview when she gets back in the country.  A friend told theReno Gazette-Journal that Danley is in the Phillipines.