You don't need a permit to buy a gun in Nevada - CNN

Authorities have not revealed the specific type of gun or guns used by the shooter, although they believe he purchased them legally.

The Law Center to Prevent Gun Violence, a gun-control advocacy group that tracks firearms legislation, gives Nevada a grade of C- on its gun laws -- lower than more restrictive states such as California or Massachusetts but higher than 25 states that scored an F.According to a Pew survey conducted in March and April, 83% of American adults said they consider gun violence in the US a big problem. But far fewer, 47%, say there would be fewer mass shootings in the US if it were harder for people to legally obtain guns.

Support for stricter gun laws often spikes temporarily following mass shootings.