Gun manufacturers' stocks are rising in the wake of the deadliest mass shooting in U.S. history, which left at least 59 people dead and more than 500 wounded.

American Outdoor Brands (AOBC), the parent company of Smith & Wesson firearms and Gemtech silencers, initially rose nearly 7 percent. Sturm, Ruger & Co. (RGR) jumped 6 percent.

Source: Yahoo Finance

Gun manufacturer shares often rally in the wake of mass shootings, as it is expected gun owners fear a regulatory crackdown.

Source: Yahoo Finance

In the wake of Sunday night's shootings at the Mandalay Bay casino, there were renewed calls from Democratic politicians to regulate firearms. Both senators from Connecticut -- where the 2012 Sandy Hook school shooting left 20 children and six teachers and staff members dead -- issued statements expressing frustration with Congressional inaction.

Damn. Sen. Chris Murphy, who reps Newtown, on Vegas shootings: "It's time for Congress to get off its ass and do something." pic.twitter.com/5WRblRdqje — Jennifer Bendery (@jbendery) October 2, 2017