Background checks -- the first step toward the purchase of a gun in Colorado -- jumped 43% in the aftermath of a shooting rampage in Aurora that killed 12 people last Friday, The Denver Post reports.
Firearms instructors also note increased interest in the training required for obtaining a concealed-carry permit.
"It's been insane," Jake Meyers, an employee at Rocky Mountain Guns and Ammo in Parker, tells The Post.
The newspaper, quoting the Colorado Bureau of Investigation, says the 2,887 background checks sought by people interested in buying a firearm between Friday and Monday represent a 43% jump over the same period the previous week.
Arizona experienced a similar jump in gun sales following a mass shooting in Tucson in January 2011 that left six people dead and 12 injured, including then-Rep. Gabrielle Giffords.
Bloomberg news reports that, according to FBI data, handgun sales in Arizona on the Monday after the weekend shooting spiked 60% over the same day the previous year.