Pictured: Chilling glimpse of mass killer's Las Vegas hotel room arsenal

As Las Vegas continues to grieve, harrowing first images have emerged from inside the gunman’s hotel room where he gunned down 59 people and injured 527 more.

Stephen Paddock used a hammer to smash the window of a room on the 32nd floor of the Mandalay Bay Resort and Casino before shooting relentlessly into the crowd below gathered for the last performance of a country music festival.

Photographs show the extent of the 64-year-old’s arsenal, including the hammer, two of the 23 guns, ammunition and a bipod used to perch a rifle through the hotel window.

A further 19 additional firearms were found in Paddock’s Nevada home.

One of the main questions surrounding the massacre is how Paddock was able to fire his weapons into the crowd at a fully automatic rate.

It’s believed the retired accountant used so-called bump stocks to allow his semi-automatic weapons to fire continuously.

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On Tuesday, Dixie GunWorx owner Chris Michel said Paddock “knew exactly what he was looking for” when he came into his store and purchased a shotgun.

It is unknown how long Paddock had been building his arsenal, but Mr Michel recalls the former accountant coming into his store a couple of times.

“He didn't set off any of my alarms, anything that I felt like there's a problem in any way, shape or form with him,” Mr Michel said.

“He came in again another time, he wanted a firearm, he knew exactly what he was looking for in the shotgun that I sold him.