Authorities in Las Vegas said there is evidence that some of the fire arms used by Stephen Paddock in Sunday night’s shooting had been tampered with.

Officials would not comment on whether or not the weapons Paddock used were fully automatic, but did confirm that's what’s known as a bump stock was affixed to one of his rifles. A bump stock turns a semi automatic rifle into a weapon that can fire almost as fast as an automatic one. 

Las Vegas Metropolitan Police Department Sheriff Joseph Lombardo said he has a growing concern about his officers facing weapons like this.

"The world has changed." Lombardo said. "And who would have ever imagined this situation. I couldn’t have imagined it. And for this individual to take it upon himself to create this chaos and harm is unspeakable."

Lombardo added that investigators have also found multiple cameras inside and around his hotel room, including on a food cart outside. He speculated that might have been used to look out for authorities.

In addition to the homicide investigations, officials said they are also evaluating their own performance when responding to Sunday night’s shooting and what could have been done differently.

Lombardo said that’s a critical procedure for any law enforcement agency after incidents like these.

"As a result of what occurred in Columbine, what occurred in Sacramento, what occurred in Boston what occurred at the pulse night club," Lombardo said. "Police response has changed."

Police expect the number of injured victims to decrease from the 500 that were reported yesterday, however the death toll remains at 59 as of Tuesday afternoon.