The theater shooting in Colorado last week continues to generate discussions about firearms in America, but it is doing more than just getting people to talk. Gun sales in Colorado have skyrocketed in the days since the Aurora, CO massacre.

James Holmes, 24, is being held in connection with the Friday morning outburst that left 12 people dead and injured dozens more. Authorities allege that Holmes opened fire shortly after the midnight screening of Batman: The Dark Knight Rises began at the Century Aurora 16 theater. Only hours later, though, locals were lining up in droves to equip themselves with the same kinds of weaponry.

Jake Meyers tells the Denver Post that he arrived for work at Rocky Mountain Guns and Ammo on early Friday to find a line of 15 to 20 people waiting outside of the store. Three days later, he said surging gun sales yielded “probably the busiest Monday all year” and that, for the first time all year, firearms classes taught by the store’s staff were booked for three weeks straight.

“It’s been insane,” Meyers says.

“A lot of it is people saying, ‘I didn’t think I needed a gun, but now I do,’ “ Meyers adds. “When it happens in your backyard, people start reassessing — ‘Hey, I go to the movies.’ “

The Denver Post reveals that, in only the three days after the shooting, the Colorado Bureau of Investigation approved background checks for 2,887 people interested in purchasing a firearm, signaling a 43 percent jump from the week before and a 39 percent increase from the same time in 2011.

“We’ve definitely had an increase,” Dion Studinski of the nearby Firing-Line gun store and shooting range confirms to the Post.

It’s not just the small-town shop owners who are thriving either. Although both the Standard Poor’s 500 and the Dow Industrial Average fell 1.9 percent and 1.7 percent, respectively, between the closing bell on Thursday and the end of Monday, the only two publicly-traded gun makers saw their shares defy the rest of the market. Smith Wesson, the makers of at least one of the weapons allegedly used by Holmes, saw their shares drop by only 0.01 percent; Strum, Ruger saw their value spike up by 3.6 percent during the same span.

Alleged shooter James Holmes made his first court appearance on Monday morning. He is expected to be charged with crimes related to the massacre next week.